Chapter XVI: Part 16

[91] PAGE 33, LINE 12. Page 33, line 9. _Augustani ... in emplastrum nigrum_....--Amongst the physicians of the Augsburg school the most celebrated were Adolphus Occo, Ambrosio Jung, and Gereone Seyler. This particular reference is to the _Pharmacopoeia Augustana_ ... _a Collegio Medico recognita_, published at Augsburg, and which ran through many editions. The recipe for the "_emplastrum nigrum vulgo Stichpflaster_" will be found on p. 182 of the seventh edition (1621-2). The recipe begins with oil of roses, colophony, wax, and includes some twenty-two ingredients, amongst them mummy, dried earthworms, and two ounces _lapidis magnetis præparati_. The recipe concludes: "Fiat Emplastrum secundùm artem. Perquàm efficax ad recentia vulnera et puncturas, vndè denominationem habet." The volume is a handsome folio not unlike Gilbert's own book, and bears at the end of the prefatory address _ad Lectorem_ identically the same _cul de lampe_ as is found on p. 44 of _De Magnete_.

The contradictions as to the alleged medicinal virtues of loadstone are well illustrated by Galen, who in his _De facultatibus_ says that loadstone is like hæmatite, which is astringent, while in his _De simplici medicina_ he says it is purgative.

[92] PAGE 33, LINE 14. Page 33, line 12. _Paracelsus in fodicationum emplastrum_.--Paracelsus's recipe for a plaster against stab-wounds is to be found in _Wundt vund Leibartznei_ ... D. Theoph. Paracelsus (Frankf., 1555, pp. 63-67).

[93] PAGE 33, LINE 17. Page 33, line 15. _Ferri vis medicinalis_.--This chapter on the medicinal virtues of iron is a summary of the views held down to that time. Those curious to pursue the subject should consult Waring's _Bibliotheca Therapeutica_ (London, 1878). Nor should they miss the rare black-letter quarto by Dr. Nicholas Monardus, of Seville, _Joyfull Newes out of the New-found Worlde_, translated by John Frampton (London, 1596), in which are recited the opinions of Galen, Rhazes, Avicenna, and others, on the medicinal properties of iron. In addition to the views of the Arabic authors, against whom his arguments are directed, Gilbert discusses those of Joannes Manardus, Curtius, and Fallopius. The treatise of Manardus, _Epistolarum medicinalium libri viginti_ (Basil., 1549), is a _résumé_ of the works of Galen and the Arabic physicians, but gives little respecting iron. Curtius (Nicolaus) was the author of a book, _Libellus de medicamentis præparatibus et purgantibus_ (Giessæ Cattorum, 1614). The works of Fallopius are _De Simplicibus Medicamentis purgentibus tractatus_ (Venet., 1566, 4to), and _Tractatus de Compositione Medicamentorum_ (Venet., 1570, 4to).

[94] PAGE 34, LINE 7. Page 34, line 3. _quorundã Arabum opiniones_.--The Arabian authorities referred to here or elsewhere by Gilbert are:

_Albategnius_ (otherwise known as Machometes Aractensis), Muhammad Ibn J[=a]bir, _Al-Batt[=a]n[=i]_.

_Avicenna_ (otherwise Abohali). Abou-'Ali al-'Hoséin ben-'Abd-Allah Ibn-Sinâ, or, shortly, _Ibn Sîna._

_Averroes._ Muhammad Ibn Ahmed Ibn-Roschd, _Abou Al-Walíd._

_Geber._ Ab[=u] M[=u]s[=a] J[=a]bir Ibn Haiy[=a]n, _Al-Tars[=u]si._

_Hali Abas._ 'Alí Ibn Al-'Abbás, _Al Majúsi_. {30}

_Rhazes_, or _Rasis_. Muhammad Ibn Zakar[=i]y[=a].

_Serapio._ Yuhanná Ibn Sarapion.

_Thebit Ben-Kora_ (otherwise Thabit Ibn Corrah). Ab[=u] Thabit Ibn Kurrah, _Al Harrani._

[95] PAGE 34, LINE 38.: Page 34, line 40. _electuarium de scoria ferri descriptum à Raze._--Rhazes or Rasis, whose Arabic name was Muhammad Ibn Zakar[=i]y[=a], wrote _De Simplicibus, ad Almansorem._ In Chap. 63 of this work he gives a recipe for a stomachic, which includes fennel, anise, origanum, black pepper, cinammon, ginger, and iron slag. In the splendid folio work of Rhazes publisht at Venice in 1542, with the title _Habes candide lector Contin[~e]tem Rasis_, Libri ultimi, cap. 295, under the heading _De Ferro,_ are set forth the virtues of iron slag: "Virtus scorie est sicut virtus scorie [a]eris sed debilior in purgãdo: et erugo ferri est stiptica: et c[~u] superpositur retinet fluxus menstruor[~u].... Ait Paulus: aqua in qua extinguitur ferr[~u] calens.... Dico: certificatus sum experientia [~q] valet contra emorryodas diabetem et fluxum menstruorum."

[96] PAGE 35, LINE 16.: Page 35, line 13. _Paulus._--This is not Fra Paolo Sarpi, nor Marco Polo, nor Paulus Jovius the historian, nor Paulus Nicolettus Venetus, but Paulus Aeginæ.

[97] PAGE 35, LINE 29.: Page 35, line 28. _Sed malè Avicenna._--The advice of Avicenna to administer a draught containing powdered loadstone, reads as follows in the Giunta edition (Venice, 1608):

Lib. ii., cap. 470, p. 356. "Magnes quid est? Est lapis qui attrahit ferrum, quum ergo aduritur, fit hæmatites, & virtus ejus est sicut virtus illius.... Datur in potu [ad bibitionem limaturæ ferri, quum retinetur in ventre scoria ferri. Ipse enim extrahit] ipsam, & associatur ei apud exitum. Et dicitur, quando in potu sumuntur ex eo tres anulusat cum mellicrato, educit solutione humorem grossum malum."

The passage is identical with that in the Venetian edition of 1486, in both of which the liquid prescribed is mellicratus--mead. Gilbert says that the iron is to be given in juice of _mercurialis_. Here he only follows Matthiolus, who, in his _Commentaries on Dioscorides_, says (p. 998 of the Basil. edition of 1598): "Sed (vt idem Auicenna scribit) proprium hujusce ferrei pharmaci antidotum, est lapis magnes drachmæ pondere potus, ex mercurialis, vel betæ succo."

Serapio, in his _De Simplicibus Medicinis_ (Brunfels' edition, Argentorati, 1531), p. 264, refers to Galen's prescription of iron scoriæ, and under the article _de lapide magnetis_, p. 260, quotes Dioscorides as follows: "Et uirtus huius lapidis est, ut quãdo dantur in potu duo onolosat ex eo c[~u] melicrato, laxat humores grossos."

The original passage in Dioscorides, _De Materia Medica,_ ch. 147 (Spengel's edition of 1829) runs: "[Greek: Tou de magnêtou lithou aristos estin ho ton sidêron eucherôs helkôn, kai tên chroan kuanizôn, puknos te kai ouk agan barus. Dunamin de echei pachous agôgon didomenos meta melikratou triôbolou baros; enioi de touton kaiontes anti haimatitou pipraskousin.]."

In the Frankfurt edition of Dioscorides, translated by Ruellius (1543), the passage is:

"Magnes lapis optimus est, qui ferrum facile trahit, colore ad coeruleum uergente, densus, nec admodum gravis. Datur cum aqua mulsa, trium obolorum pondere, ut crassos humores eliciat. Sunt qui magnetem cremat[=u] pro hæmatite vendant...."

In the _Scholia_ of Joannes Lonicerus upon Dioscorides _In Dioscoridæ {31} Anazarbei de re medica libros a Virgilio Marcello versos, Scholia nova, Ioanne Lonicero autore_ (Marburgi, 1543, p. 77), occurs the following:

"_De recremento ferri._ Cap. XLIX.

"[Greek: Skôria sidêrou]. scoria vel recrementum ferri. Quæ per ignem à ferro et cupro sordes separantur ac reijciuntur, et ab aliis metallis [Greek: skôria] uocantur. Omnis scoria, maxime uero ferri exiccat. Acerrimo aceto macerauit Galenus ferri scoriam, ac deinde excocto, pharmacum efficax confecit ad purulentas quæ multo tempore uexatæ erant, aures, admirando spectantium effectu. Ardenti scoria uel recrementum [Greek: helkusma], inquit Galenus."

See also the _Enarrationes eruditissimæ_ of Amatus Lusitanus (Venet., 1597), pp. 482 and 507, upon iron and the loadstone.

[98] PAGE 36, LINE 27. Page 36, line 29. _eijcitur_ for _ejicitur_.

[99] PAGE 37, LINE 18. Page 37, line 22. _ut Cardanus philosophatur._--Cardan's nonsense about the magnet feeding on iron is to be found in _De Subtilitate_, lib. vii. (Basil., 1611, p. 381).

[100] PAGE 38, LINE 4. Page 38, line 7. _ferramenta ... in usum navigantium._--Compare Marke Ridley's _A Short Treatise of Magneticall Bodies and Motions_ (Lond., 1613), p. _a2_ in the _Preface Magneticall_, where he speaks of the "iron-workes" used in building ships. The phraseology of Marke Ridley throws much light on the Latin terms used by Gilbert.

[101] PAGE 38, LINE 36. Page 38, line 42. _vruntur;_ changed in ink to _vrantur_ in the folio of 1600; but _uruntur_ appears in the editions of 1628 and 1633.

[102] PAGE 39, LINE 12. Page 39, line 12. _virumque;_ altered in ink to _virunque_ in all copies of the folio edition of 1600.

[103] PAGE 40, LINE 32. Page 40, line 33. _ad tantos labores exantlandos._--Pumping, as it was in mining before the invention of the steam engine, may best be realized by examining the woodcuts in the _De re metallica_ of Georgius Agricola (Basil., Froben, 1556).

[104] PAGE 40, LINE 34. Page 40, line 36. _quingentas orgyas._--Gilbert probably had in his mind the works of the Rorerbühel, in the district of Kitzbühl, which in the sixteenth century had reached the depth of 3,107 feet. See Humboldt's _Cosmos_ (Lond., 1860, vol. i., p. 149).

[105] PAGE 43, LINE 34. Page 43, line 33. _glis._--This word, here translated _grit_, does not appear to be classical Latin; it may mean _ooze or slime_.

[106] PAGE 45, LINE 25. Page 45, line 26. _Motus igitur ... quinque._ The five kinds of magnetic motions correspond in fact to the remaining sections of the book; as follows: _Coitio_, Book II.; _Directio_, Book III.; _Variatio_, Book IV.; _Declinatio_, Book V.; and _Revolutio_, Book VI.

[107] PAGE 46, LINE 7. Page 46, line 8. _Jofrancus Offusius._--The reference is to the treatise _De divina astrorum faculitate_ of Johannes Franciscus Offusius (Paris, 1570).

[108] PAGE 47, LINE 15. Page 47, line 18. _Græci vocant_ [Greek: êlektron], _quia ad se paleas trahit._ In this discussion of the names given to amber, Gilbert apparently conceives [Greek: êlektron] to be derived from the verb [Greek: helkein]; which is manifestly a doubtful etymology. There has been much discussion amongst philologists as to the derivation of [Greek: êlektron] or [Greek: êlektron], and its possible connection with the word [Greek: êlektôr]. This discussion has been somewhat obscured by the circumstance that the Greek authors unquestionably used [Greek: êlektron] (and the Latins their word _electrum_) in two different significations, some of them using these words to mean amber, others to mean a shining {32} metal, apparently of having qualities between those of gold and silver, and probably some sort of alloy. Schweigger, _Ueber das Elektron der Alten_ (Greifswald, 1848), has argued that this metal was indeed no other than platinum: but his argument partakes too much of special pleading. Those who desire to follow the question of the derivation of [Greek: êlektron] may consult the following authorities: J. M. Gessner, _De Electro Veterum_ (Commentt. Soc. Reg. Scientt. Goetting., vol. iii., p. 67, 1753); Delaunay, _Mineralogie der Alten_, Part II., p. 125; Buttmann, _Mythologus_ (Appendix I., _Ueber das Elektron_), Vol. II., p. 355, in which he adopts Gilbert's derivation from [Greek: helkein]; Beckmann, _Ursprung und Bedeutung des Bernsteinnamens Elektron_ (Braunsberg, 1859); Th. Henri Martin, _Du Succin, de ses noms divers et de ses variétés suivant les anciens_ (Mémoires de l'Académie des Inscriptions et Belles-lettres, Tome VI., 1^{re} série, 1^{re} partie, 1860); Martinus Scheins, _De Electro Veterum Metallico_ (Inaugural dissertation, Berlin, 1871); F. A. Paley, _Gold Worship in relation to Sun Worship_ (Contemporary Review, August, 1884). See also Curtius, _Grundzüge der griechischen Etymologie_, pp. 656-659. The net result of the disputations of scholars appears to be that [Greek: êlektôr] (he who shines) is a masculine form to which there corresponds the neuter form [Greek: êlektron] (that which shines). Stephanus admits the accentuation used by Gilbert, [Greek: êlektron], to be justified from the _Timæus_ of Plato; see Note to p. 61.

[109] PAGE 47, LINE 16. Page 47, line 19. [Greek: harpax] dicitur, & [Greek: chrusophoron].--With respect to the other names given to amber, M. Th. Henri Martin has written (see previous note) so admirable an account of them that it is impossible to better it. It is therefore given here entire, as follows:

"Le succin a reçu chez les anciens des noms très-divers. Sans parler du
nom de [Greek: lunkourion], lyncurium, qui peut-être ne lui appartient
pas, comme nous le montrerons plus loin, il s'est nommé chez les Grecs
le plus souvent [Greek: êlektron] au neutre,^1 mais aussi [Greek:
êlektros] au masculin^2 et même au féminin,^3 [Greek:
chrusêlektros],^4 [Greek: chrusophoros]^5 et peut-être, comme nous
l'avons vu, [Greek: chalkolithanon]; plus tard [Greek: souchion]^6 ou
[Greek: souchinos]^7, et [Greek: êlektrianos lithos];^8 plus tard
encore [Greek: berenikê], [Greek: beronikê] ou [Greek: bernikê];^9 il
s'est nommé [Greek: harpax] chez les Grecs établis en Syrie;^{10} chez
les Latins _succinum_, _electrum_, et deux variétés, _chryselectrum_ et
_sualiternicum_ {33} ou _subalternicum_;^{11} chez les Germains,
_Gless_;^{12} chez les Scythes, _sacrium_;^{13} chez les Egyptiens,
_sacal_;^{14} chez les Arabes, _karabé_^{15} ou _kahraba_;^{16} en
persan, _káruba_.^{17} Ce mot, qui appartient bien à la langue persane,
y signifie _attirant la paille_, et par conséquent exprime l'attraction
électrique, de même que le mot [Greek: harpax] des Grecs de Syrie. En
outre, le nom de _haur roumi_ (_peuplier romain_) était donné par les
Arabes, non-seulement à l'arbre dont ils croyaient que le succin était
la gomme, mais au succin lui-même. _Haur roumi_, transformé en _aurum_
par les traducteurs latins des auteurs arabes, et consondu mal à propos
avec _ambar_ ou _ambrum_, nom arabe latinisé de l'ambre gris, a produit
le nom moderne d'_ambre_, nom commun à l'_ambre jaune_ ou succin, qui
est une résine fossile, et à l'_ambre gris_, concrétion odorante qui se
forme dans les intestines des cachalots. On ne peut dire avec certitude
si le nom de basse grécité [Greek: bernikê] est la source ou le dérivé
de _Bern_, radical du nom allemand du succin (_Bernstein_). Quoi qu'il
en soit, le mot [Greek: bernikê] a produit _vernix_, nom d'une gomme
dans la basse latinité, d'où nous avons fait _vernis_.^{18}"

^1 Voyez Hérodote, III., 115; Platon, _Timée_, p. 80 c; Aristote,
_Météor._, IV., 10; Théophraste, _Hist. des plantes_, IX., 18 (19), §
2; _Des pierres_, § 28 et 29; Diodore de Sic., V., 23; Strabon, IV., 6,
n^o 2, p. 202 (Casaubon); Dioscoride, _Mat. méd._, I., 110; Plutarque,
_Questions de table_, II., 7, § 1; _Questions platoniques_, VII., 1 et
7; Lucien, _Du succin et des cygnes_; le même, _De Pastrologie_, § 19;
S. Clément, _Strom._ II., p. 370 (Paris, 1641, in-fol.); Alexandre
d'Aphr., _Quest. phys. et mor._, II., 23; Olympiodore, _Météor._, I.,
8, fol. 16, t. I., p. 197 (Ideler) et l'abréviateur d'Etienne de
Byzance au mot [Greek: Êlektrides].

^2 Voyez Sophocle, _Antigone_, v. 1038, et dans Eustathe, sur
l'_Iliade_, II., 865; Elien, _Nat. des animaux_, IV. 46; Quintus de
Smyrne, V., 623; Eustathe, sur la _Périégèse_ de Denys, p. 142
(Bernhardy), et sur l'_Odyssée_, IV., 73; et Suidas au mot [Greek:
hualê].

^3 Voyez Alexandre, _Problèmes_, sect. 1, prooem., p. 4 (Ideler);
Eustathe, sur l'_Odyssée_, IV., 73, et Tzetzès, _Chiliade_ VI., 650.

^4 Voyez Psellus, _Des pierres_, p. 36 (Bernard et Maussac).

^5 Voyez Dioscoride, _Mat. méd._, I., 110.

^6 Voyez S. Clément, _Strom._, II., p. 370 (Paris, 1641, in-fol.). Il
paraît distinguer l'un de l'autre [Greek: to souchion] et [Greek: to
êlektron], probablement parce qu'il attribue à tort au métal [Greek:
êlektron] la propriété attractive du succin.

^7 Voyez le faux Zoroastre, dans les _Géoponiques_, XV., 1, § 29.

^8 Voyez le faux Zoroastre, au même endroit.

^9 Voyez Eustathe, sur l'_Odyssée_, IV., 73; Tzetzès, _Chil._ VI., 650;
Nicolas Myrepse, _Antidotes_, ch. 327, et l'Etymol. Gud. au mot [Greek:
êlektron]. Comparez Saumaise, Exert. plin., p. 778.

^{10} Voyez Pline, XXXVII., 2, s. 11, n^o 37.

^{11} Voyez Pline, XXXVII., 2, s. 11-13, et Tacite, _Germanie_, ch. 45.
La forme _sualiternicum_, dans Pline (s. 11, n^o 33), est donnée par le
manuscrit de Bamberg et par M. Sillig (t. V., p. 390), au lieu de la
forme _subalternicum_ des éditions antérieures.

^{12} Voyez Tacite et Pline, _ll. cc._

^{13} Voyez Pline, XXXVII., 2, s. 11, n^o 40, Comp. J. Grimm, _Gesch.
der deutsch. Sprache_, Kap. x., p. 233 (Leipzig, 1848, in-8).

^{14} Pline, _l. c._

^{15} Voyez Saumaise, _De homon. hyles iatricæ_, c. 101, p. 162 (1689,
in-fol.).

^{16} Voyez Sprengel, sur Dioscoride, t. II., pp. 390-391.

^{17} Voyez M. de Sacy, cité par Buttmann, _Mythologus_, t. II., pp.
362-363.

^{18} Voyez Saumaise, _Ex. plin._, p. 778. Il n'est pas probable que le
mot [Greek: bernikê] ou [Greek: berenikê] nom du succin dans la grécité
du moyen âge, soit lié étymologiquement avec le nom propre [Greek:
berenikê], qui vient de l'adjectif macédonien [Greek: berenikos] pour
[Greek: pherenikos].

[110] PAGE 47, LINE 17. Page 47, line 20. _Mauri vero Carabem appellant, quià solebant in sacrificijs, & deorum cultu ipsum libare. Carab enim significat offerre Arabicè; ita Carabe, res oblata; aut rapiens paleas, vt Scaliger ex Abohali citat, ex linguâ Arabicâ, vel Persicâ._--The printed text, line 18, has "Non rapiens paleas," but in all copies of the folio of 1600, the "Non" has been altered in ink into "aut," possibly by Gilbert's own hand. Nevertheless the editions of 1628 and 1633 both read "Non." There appears to be no doubt that the origin of the word _Carabe_, or _Karabe_, as assigned by Scaliger, is substantially correct. As shown in the preceding note, Martin adopted this view. If any doubt should remain it will be removed by the following notes which are due to Mr. A. Houtum Schindler (member of the Institution of Electrical Engineers), of Terahan.

Reference is made to the magnetic and electric properties of stones in three early Persian lapidaries. There are three stones only mentioned, amber, loadstone, and garnet. The electric property of the diamond is not mentioned. The following extracts are from the _Tansûk nâmah_, by Nasîr ed dîn Tûsi, A.D. 1260. The two other treatises give the first extracts in the same words.

"_Kâhrubâ_, also _Kahrabâ_ [Amber],

"Is yellow and transparent, and has its name from the property, which it possesses, of attracting small, dry pieces of straw or grass, after it has been rubbed with cloth and become warm. [Note. In Persian, Kâh = straw; rubâ = the robber, hence Kâhrubâ = the straw-robber.] Some consider it a mineral, and say that it is found in the Mediterranean and Caspian seas, floating on the surface, but this is not correct. The truth is that Kâhrubâ {34} is the gum of a tree, called jôz i rûmî [_i.e._, roman nut; walnut?], and that most of it is brought from Rûm [here the Eastern Rome] and from the confines of Sclavonia and Russia. On account of its bright colour and transparency it is made into beads, rings, belt-buckles, &c. ... &c.

* * * * *

"The properties of attraction and repulsion are possessed by other substances than loadstone, for instance, by amber and bîjâdah,^1 which attract straws, feathers, etc., and of many other bodies, it can be said that they possess the power of attraction. There is also a stone which attracts gold; it has a pure yellow colour. There is also a stone which attracts silver from distances of three or two yards. There are also the stone which attracts tin, very hard, and smelling like asafoetida, the stone attracting hair, the stone attracting meat, etc., but, latterly, no one has seen these stones: no proof, however, that they do not exist."

Avicenna (Ibn Sinâ) gives the following under the heading of _Karabe_ (see _Canona Medicinæ_, Giunta edition, Venet., 1608, lib. ii., cap. 371, p. 336):

"Karabe quid est? Gumma sicut sandaraca, tendens ad citrinitatem, & albedinem, & peruietatem, & quandoque declinat ad rubedinem, quæ attrahit paleas, & [fracturas] plantarum ad se, & propter hoc nominatur Karabe, scilicet rapiens paleas, persicè.... Karabe confert tremori cordis, quum bibitur ex eo medietas aurei cum aqua frigida, & prohibet sputum sanguinis valde.... Retinet vomitum, & prohibet materias malas a stomacho, & cum mastiche confortat stomachum.... Retinet fluxum sanguinis ex matrice, & ano, & fluxum ventris, & confert tenasmoni."

Scaliger in _De Subtilitate_, _Exercitatio_ ciii., § 12, the passage referred to by Gilbert says: "Succinum apud Arabas uocatur, Carabe: quod princeps Aboali, rapiens paleas, interpretatur" (p. 163 _bis_, editio Lutetiæ, 1557).

^1 _Bîjâdah_ is classified by Muhammad B. Mansûr (A.D. 1470) and by Ibn
al Mubârak (A.D. 1520) under "stones resembling ruby"; the Tansûk nâmah
describes it in a separate chapter. From the description it can be
identified with the almandine garnet, and the method of cutting this
stone _en cabochon_, with hollow back in order to display its colour
better is specially mentioned. The Tansûk nâmah only incidentally
refers to the electric property of the _bîjâdah_ in the chapter on
loadstone, but the other two treatises specially refer to it in their
description of the stone. The one has: "_Bîjâdah_ if rubbed until warm,
attracts straws and other light bodies just as amber does"; the other:
"_Bîjâdah_, if rubbed on the hair of the head, or on the beard,
attracts straws." Surûri, the lexicographer, who compiled a dictionary
in 1599, considers the _bîjâdah_ "a red ruby which possesses the
property of attraction." Other dictionaries do not mention the
attractive property, but some authors confound the stone with amber,
calling it _Kâbrubâ_, the straw-robber. The _bîjâdah_ is not rubellite
(red tourmaline) for it is described in the lapidaries as common,
whereas rubellite (from Ceylon) has always been rare, and was unknown
in Persia in the thirteenth century.

[111] PAGE 47, LINE 21. Page 47, line 25. _Succinum seu succum._--Dioscorides regarded amber as the inspissated juice of the poplar tree. From the Frankfurt edition of 1543 (_De Medicinali materia, etc._) edited by Ruellius, we have, liber i., p. 53:

_Populus._ Cap. XCIII.

"... Lachrymam populorum commemorant quæ in Padum amnem defluat, durari, ac coire in succinum, quod electrum vocant, alii chrysophorum. id attritu jucundum odorem spirat, et aurum colore imitatur. tritum potumque stomachi ventrisque fluxiones sistit."

To this Ruellius adds the commentary:

"Succinum seu succina gutta à succo dicta, Græcis [Greek: êlektrom] [sic], esse {35} lachryma populi albæ, vel etiam nigræ quibusdam videtur, ab ejusdem arboris resina. Dioscoridi et Galeno dicta differens et [Greek: pterugophoros], id est paleas trahens, quoque vocatur, quantum ei quoque Galenus tribuit li. 37, ca. 9. Succinum scribit à quibusdam pinei generis arboribus, ut gummi à cerasis excidere autumno, et largum mitti ex Germania septentrionali, et insulis maris Germanici. quod hodie nobis est compertissimum: ad hæc liquata igni valentiore, quia à frigido intensiore concrevit. pineam aperte olet, calidum primo gradu, siccum secundo, stomachum roborat, vomitum, nauseam arcet. cordis palpitationi prodest. pravorem humorum generationem prohibet.

"Germani weiss und gelbaugstein et bre[=n]stein.

"Galli ambra vocant: vulgo in corollis precariis frequens."

In the scholia of Johann Lonicer in his edition of Dioscorides, we find, lib. i., cap. xcviii., _De nigra Populo_:

"[Greek: aigeiros], populus nigra ... idem electrum vel succinum [Greek: haigeirou] lachrymam esse adseverat [Paulus], cui præter vires quæ ab Dioscoride recensentur, tribuit etiam vim sistendi sanguinis, si tusum in potu sumatur. Avicennæ Charabe, ut colligitur ex Joanne Jacobo Manlio, est electrum hoc Dioscoridis, attestatur Brunfelsius. Lucianus planè nullum electrum apud Eridanum seu Padum inveniri tradit, quandoquidem ne populus quidem illa ab nautis ei demonstrari potuerit. Plinius rusticas transpadanas ex electro monilia gestare adfirmat, quum à Venetis primum agnoscere didicissent adversus nimirum vitia gutturis et tonsillarum. Num sit purgamentum maris, vel lachryma populi, vel pinus, vel ex radiis occidentis solis nascatur, vel ex montibus Sudinorum profluat, incertum etiam Erasmus Stella relinquit. Sudinas tamen Borussiorum opes esse constat."

Matthiolus (in _P. A. Mattioli ... Opera quæ extant omnia, hoc est Commentarii in vi libros P. Dioscoridis de materia medica_, Frankfurt, 1596, p. 133) comments on the suggestion of Galen that amber came from the _Populus alba_, and also comments on the Arabic, Greek, and Latin names of amber.

The poplar-myth is commemorated by Addison (in _Italy_) in the lines:

No interwoven reeds a garland made,
To hide his brows within the vulgar shade;
But poplar wreathes around his temples spread,
And tears of amber trickled down his head.

Amber is, however, assuredly not derived from any poplar tree: it comes from a species of pine long ago extinct, called by Göppert the _pinites succinifer_.

Gilbert does not go into the medicinal uses, real or fancied, that have been ascribed to amber in almost as great variety as to loadstone. Pliny mentions some of these in his _Natural Historie_ (English version of 1601, p. 609):

"He [Callistratus] saith of this yellow Amber, that if it be worne about the necke in a collar, it cureth feavers, and healeth the diseases of the mouth, throat, and jawes: reduced into pouder and tempered with honey and oile of roses, it is soveraigne for the infirmities of the eares. Stamped together with the best Atticke honey, it maketh a singular eyesalve for to help a dim sight: pulverized, and the pouder thereof taken simply alone, or else drunke in water with Masticke, is soveraigne for the maladies of the stomacke."

Nicolaus Myrepsus (Recipe 951, _op. citat._) gives a prescription for {36} dysentery and diabetes confiding chiefly of "Electri vel succi Nili (Nili succum appellant Arabes Karabem)."

[112] PAGE 47, LINE 22. Page 47, line 26. _Sudauienses seu Sudini._--Cardan in _De Rerum Varietate_, lib. iii., cap. xv. (Editio Basil., 1556, p. 152), says of amber:

"Colligitur in quadam penè insula Sudinorum, qui nunc uoc[=a]tur Brusci, in Prussia, nunc Borussia, juxta Veneticum sinum, & sunt orientaliores ostiis Vistulæ fluuii: ubi triginta pagi huic muneri destinati sunt," etc. He rejects the theory that it consists of hardened gum.

There exists an enormous literature concerning Amber and the Prussian amber industry. Amongst the earliest works (after Theophrastus and Pliny) are those of Aurifaber (_Bericht über Agtstein oder Börnstein_, Königsberg, 1551); Goebel (_De Succino, Libri duo, authore Severino Goebelio, Medico Doctore_, Regiomont., 1558); and Wigand (_Vera historia de Succino Borussico_, Jena, 1590). Later on Hartmann, P. J. (_Succini Prussici Physica et civilis Historia_, Francofurti, 1677); and the splendid folio of Nathaniel Sendel (_Historia Succinorum corpora aliena involventium_, Lipsiæ, 1742), with its wealth of plates illustrating amber specimens, with the various included fossil fauna and flora. Georgius Agricola (_De natura Fossilium_, liber iv.), and Aldrovandi (_Musæeum Metallicum_, pp. 411-412) must also be mentioned. Bibliographies of the earlier literature are to be found in Hartmann (_op. citat._), and in Daniel Gralath, _Elektrische Bibliothek_ (_Versuche und Abhandlungen der Naturforschenden Gesellschaft in Danzig_, Zweiter Theil, pp. 537-539, Danzig and Leipzig, 1754). See also Karl Müllenhoff, _Deutsche Altertumskunde_, vol. i., Zweites Buch, pp. 211-224, Zinn und Bernsteinhandel (Berlin, 1870), and Humboldt's _Cosmos_ (Bohn's edition, London, 1860, vol. ii., p. 493).

The ancient Greek myth according to which amber was the tears of the Heliades, shed on the banks of the river Eridanus over Phaethon, is not alluded to by Gilbert. It is narrated in well-known passages in Ovid and in Hyginus. Those interested in the modern handling of the myth should refer to Müllenhoff (_op. citat._, pp. 217-223, der Bernsteinmythus), or to that delightful work _The Tears of the Heliades_, by W. Arnold Buffum (London, 1896).

[113] PAGE 47, LINE 30. Page 47, line 36. _quare & muscos ... in frustulis quibusdam comprehensos retinet._--The occurrence of flies in amber was well known to the ancients. Pliny thus speaks of it, book xxxvii., chap. iii. (p. 608 of P. Holland's translation of 1601):

"That it doth destill and drop at the first very clear and liquid, it is evident by this argument, for that a man may see diverse things within, to wit, Pismires, Gnats, and Lizards, which no doubt were entangled and stucke within it when it was greene and fresh, and so remain enclosed within as it waxed harder."

A locust embedded in amber is mentioned in the _Musæum Septalianum_ of Terzagus (Dertonæ, 1664).

Martial's epigram (_Epigrammata_, liber vi., 15) is well known:

Dum Phaethontea formica vagatur in umbra
Implicuit tenuem succina gutta feram.

See also Hermann (Daniel), _De rana et lacerta Succino Borussiaco insitis_ {37} (Cracov., 1580; a later edition, Rigæ, 1600). The great work on _inclusa_ in amber is, however, that of Nathaniel Sendel. See the previous note.

Sir Thomas Browne must not be forgotten in this connexion. The _Pseudodoxia_ (p. 64 of the second edition, 1650) says:

"Lastly, we will not omit what Bellabonus upon his own experiment writ from Dantzich unto Mellichius, as he hath left recorded in his chapter _De Succino_, that the bodies of Flies, Pismires and the like, which are said oft times to be included in Amber, are not reall but representative, as he discovered in severall pieces broke for that purpose. If so, the two famous Epigrams hereof in Martiall are but poeticall, the Pismire of Brassavolus Imaginary, and Cardans Mousoleum for a flie, a meer phancy. But hereunto we know not how to assent, as having met with some whose reals made good their representments." See also Pope's _Epistle to Dr. Arbuthnot_, line 169.

[114] PAGE 47, LINE 34. Page 47, line 40. _Commemorant antiqui quod succinum festucas et paleas attrahit._--Pliny (book xxxvii., chap. ii., p. 606 of the English edition of 1601) thus narrates the point:

"Hee [_Niceas_] writeth also, that in Aegypt it [amber] is engendered.... Semblably in Syria, the women (saith hee) make wherves of it for their spindles, where they use to call it Harpax, because it will catch up leaves, straws, and fringes hanging to cloaths."

p. 608. "To come to the properties that Amber hath, If it bee well rubbed and chaufed betweene the fingers, the potentiall facultie that lieth within, is set on work, and brought into actual operation, whereby you shall see it to drawe chaffe strawes, drie leaves, yea, and thin rinds of the Linden or Tillet tree, after the same sort as loadstone draweth yron."

[115] PAGE 47, LINE 36. Page 47, line 42. _Quod etiam facit Gagates lapis._--The properties of Jet were well known to the mediæval writers. _Julius Solinus_ writes in _De Mirabilibus_, chapter xxxiv., _Of Britaine_ (English version of 1587 by A. Golding):

"Moreover to the intent to passe the large aboundance of sundry mettals (whereof Britaine hath many rich mynes on all sides), Here is store of the stone called Geate, and y^e best kind of it. If ye demaund y^e beautie of it, it is a black Jewell: if the qualitie, it is of no weight: if the nature, it burneth in water, and goeth out in Oyle; if the power, rubbe it till it be warme, and it holdeth such things as are laide to it; as Amber doth. The Realme is partlie inhabited of barbarous people, who even frõ theyr childhoode haue shapes of divers beastes cunninglye impressed and incorporate in theyr bodyes, so that beeing engraued as it were in theyr bowels, as the man groweth, so growe the marks painted vpon him...."

Pliny describes it as follows (p. 589, English edition of 1601):

"The Geat, which otherwise we call Gagates, carrieth the name of a toune and river both in Lycia, called Gages: it is said also, that the sea casteth it up at a full tide or high water into the Island Leucola, where it is gathered within the space of twelve stadia, and no where else: blacke it is, plaine and even, of a hollow substance in manner of the pumish stone, not much differing from the nature of wood; light, brittle, and if it bee rubbed or bruised, of a strong flavour." (Book xxxvi., chap. xviii.)

In the Commentary of Joannes Ruellius upon Dioscorides, _Pedanii Dioscoridis Anazarbei de medicinali materia libri sex, Ioanne Ruellio Suessionensi interprete_ ... (Frankfurt, 1543, fol., liber quintus, cap. xcii.) is the following description:

{38} "In Gagatarum lapidum genere, præferendus qui celeriter accenditur, et odorem bituminis reddit. niger est plerunque, et squalidus, crustosus, per quam levis. Vis ei molliendi, et discutiendi. deprehendit sonticum morbum suffitus, recreatque uuluæ strangulationes. fugat serpentes nidore. podagricis medicaminibus, et a copis additur. In Cilicia nasci solet, qua influens amnis in mare effunditur, proxime oppidum quod Plagiopolis dicitur. vocatur autem et locus et amnis Gagas, in cujus faucibus ii lapides inveniuntur.

"Gagates lapis colore atro, Germanis Schwartzer augstein, voce parum depravata, dicitur. odore dum uritur bituminis, siccat, glutinat, digerit admotus, in corollis precariis et salinis frequens."

And in the _Scholia_ upon Dioscorides of Joannes Lonicer (Marpurgi, 1643, cap. xcvii., p. 80) is the following:

"_De Gagate Lapide._ Ab natali solo, urbe nimirum Gagae Lyciae nomen habet. Galenus se flumen isthuc et lapidem non invenisse, etiamsi naui parua totam Lyciam perlustravit: ait, se autem in caua Syria multos nigros lapides invenisse glebosos, qui igni impositi, exiguam flammam gignerent. Meminit hujus Nicander in Theriacis nempe suffitum hujus abigere venenata."

There is also a good account of _Gagates_ (and of Succinum) by Langius, _Epistola_ LXXV., p. 454, of the work _Epistolarum medicinalium volumen tripartitum_ (Francofurti, 1589).

[116] PAGE 47, LINE 39. Page 47, line 45. _Multi sunt authores moderni._--The modern authors who raised Gilbert's wrath by ignorantly copying out all the old tales about amber, jet, and loadstone, instead of investigating the facts, were, as he says at the beginning of the chapter, some theologians, and some physicians. He seems to have taken a special dislike to Albertus Magnus, to Puteanus (Du Puys), and to Levinus Lemnius.

[117] PAGE 47, LINE 39. Page 47, line 46. _& gagate._--The editions of 1628 and 1633 both read _ex gagate_.

[118] PAGE 48, LINE 14. Page 48, line 16. _Nam non solum succinum, & gagates (vt illi putant) allectant corpuscula._--The list of bodies known to become electrical by friction was not quite so restricted as would appear from this passage. Five, if not six, other minerals had been named in addition to amber and jet.

(1.) _Lyncurium._ This stone, about which there has been more obscurity and confusion than about any other gem, is supposed by some writers to be the tourmaline, by others a jacinth, and by others a belemnite. The ancients supposed it to be produced from the urine of the lynx. The following is the account of Theophrastus, _Theophrastus's History of Stones. With an English Version_ ..., by "Sir" John Hill, London, 1774, p. 123, ch. xlix.-l. "There is some Workmanship required to bring the Emerald to its Lustre, for originally it is not so bright. It is, however, excellent in its Virtues, as is also the _Lapis Lyncurius_, which is likewise used for engraving Seals on, and is of a very solid Texture, as Stones are; it has also an attractive Power, like that of Amber, and is said to attract not only Straws and small pieces of Sticks, but even Copper and Iron, if they are beaten to thin pieces. This Diocles affirms. The _Lapis Lyncurius_ is pellucid, and of a fire Colour." See also W. Watson in _Philos. Trans._, 1759, L. i., p. 394, _Observations concerning the Lyncurium of the ancients_.

(2.) _Ruby._

(3.) _Garnet._ The authority for both these is Pliny, _Nat. Hist._, book xxxvii., chap. vii. (p. 617 of English edition of 1601).

{39} "Over and besides, I find other sorts of Rubies different from those above-named;... which being chaufed in the Sun, or otherwise set in a heat by rubbing with the fingers, will draw unto them chaffe, strawes, shreads, and leaves of paper. The common Grenat also of Carchedon or Carthage, is said to doe as much, although it be inferiour in price to the former."

(4.) _Jasper._ Affaytatus is the authority, in _Fortunii Affaitati Physici atque Theologi ... Physicæ & Astronomicæ c[=o]siderationes_ (Venet., 1549), where, on p. 20, he speaks of the magnet turning to the pole, likening it to the turning of a "palea ab Ambro vel Iaspide et hujuscemodi lapillis lucidis."

(5.) _Lychnis._ Pliny and St. Isidore speak of a certain stone _lychnis_, of a scarlet or flame colour, which, when warmed by the sun or between the fingers, attracts straws or leaves of papyrus. Pliny puts this stone amongst carbuncles, but it is much more probably _rubellite_, that is to say, red tourmaline.

(6.) _Diamond._ In spite of the confusion already noted, _à propos_ of _adamas_ (Note to p. 47), between loadstone and diamond, there seems to be one distinct record of an attractive effect having been observed with a rubbed diamond. This was recorded by Fracastorio, _De sympathia et antipathia rerum_ (Giunta edition, Venice, MDLXXIIII, chap. v., p. 60 _verso_), "cujus rei & illud esse signum potest, cum confricata quædã vt Succinum, & Adamas fortius furculos trahunt." And (on p. 62 _recto_); "nam si per similitudine (vt supra diximus) fit hæc attractio, cur magnes non potius magnetem trahit, [~q] ferrum, & ferrum non potius ad ferrum movetur, quàm ad magnetem? quæ nam affinitas est pilorum, & furculorum cum Electro, & Adamante? præsertim [~q] si cum Electro affines sunt, quomodo & cum Adamante affinitatem habebunt, qui dissimilis Electro est?" An incontestable case of the observation of the electrification of the diamond occurs in Gartias ab Horto. The first edition of his _Historia dei Semplici Aromati_ was publisht at Goa in India in 1563. In chapter xlviii. on the Diamond, occur these words (p. 200 of the Venetian edition of 1616): "Questo si bene ho sperimentato io più volte, che due Diamanti perfetti fregati insieme, si vniscono di modo insieme, che non di leggiero li potrai separare. Et ho parimente veduto il Diamante dopo di esser ben riscaldato, tirare à se le festuche, non men, che si faccia l'elettro." See also Aldrovandi, _Musæum Metallicum_ (Bonon., 1648, p. 947).

Levinus Lemnius also mentions the Diamond along with amber. See his _Occulta naturæ miracula_ (English edition, London, 1658, p. 199).

[119] PAGE 48, LINE 16. Page 48, line 18. _Iris gemma._--The name _iris_ was given, there can be little doubt, to clear six sided prisms of rock-crystal (quartz), which, when held in the sun's beams, cast a crude spectrum of the colours of the rainbow. The following is the account of it given in Pliny, book xxxvii., chap. vii. (p. 623 of the English version of 1601):

"... there is a stone in name called Iris: digged out of the ground it is in a certaine Island of the red sea, distant from the city Berenice three score miles. For the most part it resembleth Crystall: which is the reason that some hath tearmed it the root of Crystall. But the cause why they call it Iris, is, That if the beames of the Sunne strike upon it directly within house, it doth send from it against the walls that bee neare, the very resemblance both in forme and also in colour of a rainebow; and eftsoones it will chaunge the same in much varietie, to the great admiration of them that behold it. For certain it is knowne, that six angles it hath in manner of the Crystall: but they say that some of them have their sides rugged, and the same {40} unequally angled: which if they be laid abroad against the Sunne in the open aire, do scatter the beames of the Sunne, which light upon them too and fro: also that others doe yeeld a brightnes from themselves, and thereby illuminat all that is about them. As for the diverse colours which they cast forth, it never happeneth but in a darke or shaddowie place: whereby a man may know, that the varietie of colours is not in the stone Iris, but commeth by the reverberation of the wals. But the best Iris is that which representeth the greatest circles upon the wall, and those which bee likest unto rainebowes indeed."

In the English translation of Solinus's _De Mirabilibus_ (_The excellent and pleasant worke of Julius Solinus containing the noble actions of humaine creatures, the secretes and providence of nature, the descriptions of countries ... tr. by A. Golding, gent._, Lond., 1587), chapter xv. on Arabia has the following:

"Hee findeth likewise the Iris in the Red sea, sixe cornered as the Crystall: which beeing touched with the Sunnebeames, casteth out of him a bryght reflexion of the ayre like the Raynebowe."

Iris is also mentioned by Albertus Magnus (_De mineralibus_, Venet., 1542, p. 189), by Marbodeus Gallus (_De lapidibus_, Par. 1531, p. 78), who describes it as "crystallo simulem sexangulam," by Lomatius (_Artes of curious Paintinge_, Haydocke's translation, Lond., 1598, p. 157), who says, "... the Sunne, which casting his beames vpon the _stone Iris_, causeth the _raine-bowe_ to appeare therein ...," and by "Sir" John Hill (_A General Natural History_, Lond., 1748, p. 179).

Figures of the Iris given by Aldrovandi in the _Musæum Metallicum_ clearly depict crystals of quartz.

[120] PAGE 48, LINE 16. Page 48, line 18. _Vincentina, & Bristolla (Anglica gemma siue fluor)_. This is doubtless the same substance as the _Gemma Vincentij rupis_ mentioned on p. 54, line 16 (p. 54, line 18, of English Version), and is nothing else than the so-called "Bristol diamond," a variety of dark quartz crystallized in small brilliant crystals upon a basis of hæmatite. To the work by Dr. Thomas Venner (Lond., 1650), entitled _Via Recta_ or the _Bathes of Bathe_, there is added an appendix, _A Censure concerning the water of Saint Vincents Rocks neer Bristol (Urbs pulchra et Emporium celebre)_, in which, at p. 376, occurs this passage: "This Water of Saint _Vincents_ Rock is of a very pure, cleare, crystalline substance, answering to those crystalline Diamonds and transparent stones that are plentifully found in those Clifts."

In the _Fossils Arranged_ of "Sir" John Hill (Lond., 1771), p. 123, is the following entry: "Black crystal. Small very hard heavy glossy. Perfectly black, opake. Bristol (grottos, glass)" referring to its use.

The name _Vincentina_ is not known as occurring in any mineralogical book. Prof. H. A. Miers, F.R.S., writes concerning the passage: "_Anglica gemma sive fluor_ seems to be a synonym for _Bristolla_, or possibly for _Vincentina et Bristolla_. Both quartz and fluor are found at Clifton. In that case Vincentina and Bristolla refer to these two minerals, and if so one would expect Bristolla to be the Bristol Diamond, and Vincentina to be the comparatively rare Fluor spar from that locality."

At the end of the edition of 1653 of Sir Hugh Plat's _Jewel House of Art and Nature_, is appended _A rare and excellent Discourse of Minerals, Stones, Gums, and Rosins; with the vertues and use thereof_, By D. B. _Gent_. Here, p. 218, we read:

"We have in England a stone or mineral called a Bristol stone (because {41} many are found thereabouts) which much resembles the Adamant or Diamond, which is brought out of Arabia and Cyprus; but as it is wanting of the same hardnesse, so falls it short of the like vertues."

[121] PAGE 48, LINE 18. Page 48, line 19. _Crystallus._--Rock-crystal. Quartz. Pliny's account of it (Philemon Holland's version of 1601, p. 604) in book xxxvii., chap, ii., is:

"As touching Crystall, it proceedeth of a contrarie cause, namely of cold; for a liquor it is congealed by extreame frost in manner of yce; and for proofe hereof, you shall find crystall in no place els but where the winter snow is frozen hard: so as we may boldly say, it is verie yce and nothing else, whereupon the Greeks have give it the right name Crystallos, _i._ Yce.... Thus much I dare my selfe avouch, that crystall groweth within certaine rockes upon the Alps, and these so steepe and inaccessible, that for the most part they are constrained to hang by ropes that shall get it forth."

[122] PAGE 48, LINE 18. Page 48, line 20. _Similes etiam attrahendi vires habere videntur vitrum ... sulphur, mastix, & cera dura sigillaris._ If, as shown above, the electric powers of diamond and ruby had already been observed, yet Gilbert was the first beyond question to extend the list of _electrics_ beyond the class of precious stones, and his discovery that _glass_, _sulphur_, and _sealing-wax_ acted, when rubbed, like amber, was of capital importance. Though he did not pursue the discovery into mechanical contrivances, he left the means of that extension to his followers. To Otto von Guericke we owe the application of sulphur to make the first electrical machine out of a revolving globe; to Sir Isaac Newton the suggestion of glass as affording a more mechanical construction.

Electrical attraction by natural products other than amber after they have been rubbed must have been observed by the primitive races of mankind. Indeed Humboldt in his _Cosmos_ (Lond., 1860, vol. i., p. 182) records a striking instance:

"I observed with astonishment, on the woody banks of the Orinoco, in the sports of the natives, that the excitement of electricity by friction was known to these savage races, who occupy the very lowest place in the scale of humanity. Children may be seen to rub the dry, flat and shining seeds or husks of a trailing plant (probably a _Negretia_) until they are able to attract threads of cotton and pieces of bamboo cane."

[123] PAGE 48, LINE 23. Page 48, line 25. _arsenicum_.--This is _orpiment_. See the _Dictionary of metallick words_ at the end of Pettus's _Fleta Minor_.

[124] PAGE 48, LINE 23. Page 48, line 26. _in convenienti coelo sicco_.--The observation that only in a dry climate do rock-salt, mica, and rock-alum act as electrics is also of capital importance. Compare page 56.

[125] PAGE 48, LINE 27. Page 48, line 31. _Alliciunt hæc omnia non festucas modo & paleas._--Gilbert himself marks the importance of this discovery by the large asterisk in the margin. The logical consequence was his invention of the first _electroscope_, the _versorium non magneticum_, made of any metal, figured on p. 49.

[126] PAGE 48, LINE 34. Page 48, line 36. _quod tantum siccas attrahat paleas, nec folia ocimi._--This silly tale that basil leaves were not attracted by amber arose in the _Quæstiones Convivales_ of Plutarch. It is repeated by Marbodeus and was quoted by Levinus Lemnius as true. Gilbert denounced it as nonsense. Cardan (_De Subtilitate_, Norimb., 1550, p. 132) had already contradicted the fable. "Trahit enim," he says, "omnia levia, paleas, festucas, ramenta {42} tenuia metallorum, & ocimi folia, perperam contradicente Theophrasto." Sir Thomas Browne specifically refuted it. "For if," he says, "the leaves thereof or dried stalks be stripped into small strawes, they arise unto Amber, Wax, and other Electricks, no otherwise then those of Wheat or Rye."

[127] PAGE 48, LINE 34. Page 48, line 38. _Sed vt poteris manifestè experiri...._

Gilbert's experimental discoveries in electricity may be summarized as follows:

1. The generalization of the class of _Electrics_.
2. The observation that damp weather hinders electrification.
3. The generalization that electrified bodies attract everything,
including even metals, water, and oil.
4. The invention of the non-magnetic _versorium_ or electroscope.
5. The observation that merely warming amber does not electrify it.
6. The recognition of a definite class of _non-electrics_.
7. The observation that certain electrics do not attract if roasted or
burnt.
8. That certain electrics when softened by heat lose their power.
9. That the electric effluvia are stopped by the interposition of a
sheet
of paper or a piece of linen, or by moist air blown from the mouth.
10. That glowing bodies, such as a live coal, brought near excited amber
discharge its power.
11. That the heat of the sun, even when concentrated by a burning mirror,
confers no vigour on the amber, but dissipates the effluvia.
12. That sulphur and shell-lac when aflame are not electric.
13. That polish is not essential for an electric.
14. That the electric attracts bodies themselves, not the intervening
air.
15. That flame is not attracted.
16. That flame destroys the electrical effluvia.
17. That during south winds and in damp weather, glass and crystal, which
collect moisture on their surface, are electrically more interfered
with than amber, jet and sulphur, which do not so easily take up
moisture on their surfaces.
18. That pure oil does not hinder production of electrification or
exercise
of attraction.
19. That smoke is electrically attracted, unless too rare.
20. That the attraction by an electric is in a straight line toward it.

[128] PAGE 48, LINE 35. Page 48, line 39. _quæ sunt illæ materiæ._--Gilbert's list of electrics should be compared with those given subsequently by Cabeus (1629), by Sir Thomas Browne (1646), and by Bacon. The last-named list occurs in his _Physiological Remains_, published posthumously in 1679; it contains nothing new. Sir Thomas Browne's list is given in the following passage, which is interesting as using for the first time in the English language the noun _Electricities_:

"Many stones also both precious and vulgar, although terse and smooth, have not this power attractive; as Emeralds, Pearle, Jaspis, Corneleans, Agathe, Heliotropes, Marble, Alablaster, Touchstone, Flint and Bezoar. Glasse attracts but weakely though cleere, some slick stones and thick glasses indifferently: Arsenic but weakely, so likewise glasse of Antimony, but Crocus Metallorum not at all. Saltes generally but weakely, as Sal Gemma, Alum, and also Talke, nor very discoverably by any frication: but if gently warmed at the fire, and wiped with a dry cloth, they will better discover their Electricities." _(Pseudodoxia Epidemica_, p. 79.)

In the _Philosophical Transactions_, vol. xx., p. 384, is _A Catalogue of Electrical Bodies_ by the late Dr. Rob. Plot. It begins "Non solum succinum," and ends "alumen rupeum," being identical with Gilbert's list except that he calls "Vincentina & Bristolla" by the name "Pseudoadamas Bristoliensis."

[129] PAGE 49, LINE 25. Page 49, line 30. _non dissimili modo._--The _modus_ {43} _operandi_ of the electrical attractions was a subject of much discussion; see Cardan, _op. citat._

[130] PAGE 51, LINE 2. Page 51, line 1. _appellunt._--This appears to be a misprint for _appelluntur_.

[131] PAGE 51, LINE 22. Page 51, line 23. _smyris._--Emery. This substance is mentioned on p. 22 as a magnetic body.

[132] PAGE 52, LINE 1. Page 51, line 46. _gemmæ ... vt Crystallus, quæ ex limpidâ concreuit._ See the note to p. 48.

[133] PAGE 52, LINE 30. Page 52, line 32. _ammoniacum._--Ammoniacum, or Gutta Ammoniaca, is described by Dioscorides as being the juice of a ferula grown in Africa, resembling galbanum, and used for incense.

"_Ammoniack_ is a kind of Gum like Frankincense; it grows in Lybia, where _Ammon's_ Temple was." Sir Hugh Plat's _Jewel House of Art and Nature_ (Ed. 1653, p. 223).

[134] PAGE 52, LINE 38. Page 52, line 41. _duæ propositæ sunt causæ ... materia & forma._--Gilbert had imbibed the schoolmen's ideas as to the relations of matter and form. He had discovered and noted that in the magnetic attractions there was always a verticity, and that in the electrical attractions the rubbed electrical body had no verticity. To account for these differences he drew the inference that since (as he had satisfied himself) the magnetic actions were due to _form_, that is to say to something immaterial--to an "imponderable" as in the subsequent age it was called--the electrical actions must necessarily be due to _matter_. He therefore put forward his idea that a substance to be an electric must necessarily consist of a concreted humour which is partially resolved into an effluvium by attrition. His discoveries that electric actions would not pass through flame, whilst magnetic actions would, and that electric actions could be screened off by interposing the thinnest layer of fabric such as sarcenet, whilst magnetic actions would penetrate thick slabs of every material except iron only, doubtless confirmed him in attributing the electric forces to the presence of these effluvia. See also p. 65. There arose a fashion, which lasted over a century, for ascribing to "humours," or "fluids," or "effluvia," physical effects which could not otherwise be accounted for. Boyle's tracts of the years 1673 and 1674 on "effluviums," their "determinate nature," their "strange subtilty," and their "great efficacy," are examples.

[135] PAGE 53, LINE 9. Page 53, line 11. _Magnes vero...._--This passage from line 9 to line 24 states very clearly the differences to be observed between the magnetical and the electrical attractions.

[136] PAGE 53, LINE 36. Page 53, line 41. _succino calefacto._--Ed. 1633 reads _succinum_ in error.

[137] PAGE 54, LINE 9. Page 54, line 11. _Plutarchus ... in quæstionibus Platonicis._--The following Latin version of the paragraph in _Quæstio sexta_ is taken from the bilingual edition publisht at Venice in 1552, p. 17 _verso_, liber vii., cap. 7 (or, _Quæstio Septima_ in Ed. Didot, p. 1230).

"Electrum uero quæ apposita sunt, nequaquàm trahit, quem admodum nec lapis ille, qui sideritis nuncupatur, nec quicqu[=a] à seipso ad ea quæ in propinquo sunt, extrinsecus assilit. Verum lapis magnes effluxiones quasdam tum graves, tum etiam spiritales emittit, quibus aer continuatus & iunctus repellitur. Is deinceps alium sibi proximum impellit, qui in orbem circum actus, atque ad inanem locum rediens, ui ferrum fecum rapit & trahit. At Electrum uim quandam flammæ similem & spiritalem continet, quam quidem {44} tritu summæ partis, quo aperiuntur meatus, foras eijcit. Nam leuissima corpuscula & aridissima quæ propè sunt, sua tenuitate atque imbecillitate ad seipsum ducit & rapit, cum non sit adeo ualens, nec tantum habeat ponderis & momenti ad expellendam aeris copiam, ut maiora corpora more Magnetis superare possit & uincere."

[138] PAGE 54, LINE 16. Page 54, line 18. _Gemma Vincentij rupis._--See the note to p. 48 _supra_, where the name _Vincentina_ occurs.

[139] PAGE 54, LINE 30. Page 54, line 35. _orobi._--The editions of 1628 and 1633 read _oribi_.

[140] PAGE 55, LINE 34. Page 55, line 42. _in euacuati._--The editions of 1628 and 1633 read _inevacuati_.

[141] PAGE 58, LINE 21. Page 58, line 25. _assurgentem vndam ... declinat ab F._--These words are wanting in the Stettin editions.

[142] PAGE 59, LINE 9. Page 59, line 9. _fluore._--This word is conjectured to be a misprint for _fluxu_ but it stands in all editions.

[143] PAGE 59, LINE 22. Page 59, line 25. _Ruunt ad electria._--This appears to be a slip for _electrica_, which is the reading of the editions of 1628 and 1633.

[144] PAGE 60, LINE 7. Page 60, line 9. _tan[=q] materiales radij._--The suggestion here of material _rays_ as the _modus operandi_ of electric forces seems to foreshadow the notion of electric lines of force.