Chapter M: F. Capitaine, who, acting upon a suggestion made by Liebig, some twenty (7)

_Pur._ The best indigo is that which has the deepest purple colour, that assumes the brightest coppery hue when rubbed with the nail; its fracture is homogeneous, compact, fine-grained, and coppery; its powder is of an intensely deep blue tint, and light enough to swim on water; and it leaves only a fine streak when rubbed upon a piece of white paper. In general, when indigo is in hard, dry lumps of a dark colour, it is considered of bad or inferior quality. Indigo, when in hard or brittle lumps, or in dust or small bits, is often adulterated with sand, pulverised slate, and other earthy substances.

_Estimation._ Various methods for estimating the value of samples of indigo have been proposed, but none of them can be depended upon to give perfectly accurate results. The plan recommended by O'Neill[353] is perhaps the best; it is performed as follows:--

[Footnote 353: See 'Dictionary of Calico Printing and Dyeing.']

Weigh 25 gr. of a fair sample of the indigo finely ground; and to soften or disintegrate it still further, boil it for a short time with weak caustic soda, and then, if there be any soft lumps or clots, strain through calico; mix this with 3 quarts of water in a narrow-necked bottle which it will nearly fill, and add 400 gr. of quicklime, which has been slaked as perfectly as possible; shake well up and add a 1000 gr. measure of solution of green copperas (protosulphate of iron) at 30° Twaddell; cork the bottle closely, and leave it for three days, frequently shaking it in the interval. The indigo will be dissolved by this time; 1 quart of the clear solution is drawn off, shaken up in a bottle to oxidise it, acidified with acetic acid, and the pure indigo (INDIGOTIN) collected upon a filter, dried, and weighed. Four times the weight of the pure indigo is the per-centage of indigo in the sample.

_Uses._ As a dye stuff indigo is of great importance, both from the beauty and permanence of the colour it yields, and from the ease with which it is applied to fabrics of all materials. As a medicine it has been employed in various affections of a spasmodic character, as chorea, convulsions, epilepsy, hysteria, &c. In large quantities it often induces giddiness, vomiting, and diarrh[oe]a; and when continued for sometime, muscular twitchings, resembling those arising from strychnine.--_Dose._ Beginning at about 15 gr., and gradually increased to 1, 2, or even 3 dr., at which it should be continued for 3 or 4 months; made into an electuary with honey or sugar, to which some aromatic may be added. See INDIGO DYE, INDIGOTIN, &c.

=Indigo, Sul'phate of.= _Syn._ SULPHINDYLIC ACID, SULPHINDIGOTIC A., SAXONY BLUE, SOLUBLE INDIGO.

_Prep._ By gradually adding indigo (in fine powder), 1 part, to fuming sulphuric acid (Nordhausen sulphuric acid), 5 parts, or oil of vitriol, 8 parts contained in a stone-ware vessel placed in a tub of very cold water, to prevent the mixture heating; the ingredients are stirred together with a glass rod at short intervals until the solution is complete, after which the whole is allowed to repose for about 48 hours, by which time it becomes a homogeneous pasty mass of an intense blue colour, which in a dull light appears nearly black.

_Obs._ In this state it forms 'BARTH'S BLUE,' or the 'CHEMIC BLUE' or 'INDIGO COMPOSITION' of the dyer. Diluted with about twice its weight of soft water, it is converted into the 'SAXONY BLUE' or 'LIQUID BLUE' of the shops, also used for dyeing. When commercial sulphate of indigo is diffused through a large quantity of water, nearly boiling, and wool (old white flannel rags, &c.) is macerated in it for some time, the latter absorbs the whole of the sulphate and is dyed blue, whilst the liquor assumes a greenish-blue colour. Wool, so prepared, when well rinsed in cold water, and boiled for some minutes in a large quantity of that liquid containing 1% or 2% of carbonate of potassa, or a quantity equal to about 1-3rd that of the indigo originally employed, gives up its blue colour, and becomes of a dull brown. The liquid is now a rich blue-coloured solution of sulphindylate of potassa, from which the salt may be obtained by cautious evaporation. This compound is prepared on the large scale, by diluting sulphate of indigo with about 12 times its weight of soft water, and imperfectly saturating the solution with carbonate of potassa; the sulphindylate falls down as a dark-blue coppery-looking powder, soluble in 140 parts of cold water and in about 90 parts of boiling water. This substance is kept both in the moist and dry state, and is known in commerce under the respective names of 'DISTILLED INDIGO,' 'PRECIPITATED INDIGO,' 'SOLUBLE INDIGO,' 'INDIGO PASTE,' 'BLUE CARMINE,' 'DISTILLED BLUE,' 'SOLUBLE BLUE,' &c. It is extensively used in dyeing; and when mixed with starch, whilst in the moist state, and made into cakes or knobs, it constitutes the finest variety of the 'BLUE' used by laundresses for tinging linen. The ammonia and soda salts may be prepared in the same way as the potassa salt, by substituting the carbonates of those bases for carbonate of potassa. The ammonia salt is very soluble.

=INDIGO BLUE.= See INDIGOTIN.

=INDIGO DYE.= There are two methods of preparing solutions of indigo for dyeing.--1. By deoxidising it, and then dissolving it in alkaline menstrua.--2. By dissolving it in sulphuric acid. The former method is used in preparing the ordinary INDIGO VAT of the dyers.

1. _a._ (COLD VAT.) Take of indigo, in fine powder, 1 lb.; green copperas (clean cryst.), 2-1/2 to 3 lbs.; newly slaked lime, 3-1/2 to 4 lbs.; triturate the powdered indigo with a little water or an alkaline lye, then mix it with some hot water, add the lime, and again well mix, after which stir in the solution of copperas, and agitate the whole thoroughly at intervals for 24 hours. A little caustic potassa or soda is frequently added, and a corresponding portion of lime omitted. For use, a portion of this 'preparation vat' is ladled into the 'dyeing vat,' as wanted. After being employed for some time, the vat must be refreshed with a little more copperas and fresh-slaked lime, when the sediment must be well stirred up, and the whole thoroughly mixed together. This is the common vat for cotton.

_b._ (POTASH VAT.) Take indigo, in fine powder, 12 lbs.; madder, 8 lbs.; bran, 9 lbs.; 'potash,' 24 lbs.; water at 125° Fahr., 120 cubic feet; mix well; at the end of about 36 hours add 14 lbs. more potash, and after 10 or 12 hours longer further add 10 lbs. of potash, and rouse the whole up well; as soon as the fermentation and reduction of the indigo are well developed, which generally takes place in about 72 hours, add a little fresh-slaked lime. This vat dyes very quickly, and the goods lose less of their colour in alkaline and soapy solutions than when dyed in the common vat. It is well adapted for woollen goods.

_c._ (WOOD VAT.) As the last, but employing wood instead of madder; the vat is 'set' at 160° Fahr., and kept at that temperature until the deoxidation and solution of the indigo has commenced. The last two are also called the 'warm vat.'

_d._ (PASTEL VAT.) This is 'set' with a variety of wood which grows in France, and which is richer in colouring matter than the plant commonly known as 'wood.'

_e._ (SCHÜTZENBERGER and DE LALANDE'S VAT.) It is known that the low stage of oxidation of sulphur obtained on the reduction of sulphurous acid with zinc, dissolves indigo. On this reaction the following proceedings for dyeing and printing with indigo are founded:--To prepare the reducing liquid, a solution of bisulphite of soda at 35° B. is brought in contact with sheet zinc in a closed vessel, of which the liquid should occupy only one fourth. After the lapse of an hour the zinc is precipitated from the clear liquid by means of milk of lime. It is then diluted or decanted, or filtered with exclusion of air.

The clear liquid is then poured upon the ground indigo, with the addition of the needful soda and lime. One kilo of indigo yields in this manner a very concentrated vat of from 10 to 15 litres. Cotton is dyed cold, and wool with the aid of heat. A vat is filled with water, and a suitable quantity of the above indigo mixture introduced, when the dyeing can be performed at once. The excess of the low sulphur acid dissolves the froth which appears on the surface. During the process of dyeing, further quantities of indigo can be added as required. Cotton can be rapidly and easily dyed in this manner; and in the case of wool, the dyer escapes the many disadvantages of the hot vat and obtains brighter and clearer shades. To print a fast blue the alkaline solution of the reduced indigo is printed on with an excess of the reducing agent, aged for twelve to twenty-four hours, washed and soaped. In comparison with the old process there is a saving of indigo to the extent of 50 to 60 per cent.; the shades are richer and the impressions sharper. The colour requires no subsequent treatment, and can therefore be printed on simultaneously with most other colours.

_Obs._ Wool, silk, linen, and cotton, may each be dyed blue in the indigo vat. The goods, after being passed through a weak alkaline solution, are subjected to the action of the vat for about fifteen minutes; they are then freely exposed to the air; the immersion in the vat and the exposure are repeated until the colour becomes sufficiently deep. Wood and madder improve the richness of the dye. Other deoxidising substances, besides those above mentioned, may be used to effect the solution of the indigo; thus a mixture of caustic soda, grape sugar, indigo, and water, is often employed on the Continent for this purpose; and orpiment lime, and pearlash are also occasionally used. When properly prepared, the indigo vat may be kept in action for several months by the addition of one or other of its constituents, as required. An excess of either copperas or lime should be avoided.

2. Solution of sulphate of indigo is added to water, as required, and the goods, previously boiled with alum, are then immersed in it, and the boiling and immersion are repeated until the wool becomes sufficiently dyed.

_Obs._ With this every shade of blue may be dyed, but it is most commonly employed to give a ground to logwood blues. The colouring matter has affinity for woollen and silk with or without 'mordant,' but none for cotton. A solution of soluble indigo (sulphindylate of potassa or soda), in water very slightly acid with sulphuric acid, imparts a very fine blue to cloth, superior in tint to that given by the simple sulphate. See DYEING, &c.

=INDIGO PUR'PLE.= _Syn._ PH[OE]NICINE. The name given by Mr Crum to the purple precipitate obtained by filtration from a solution of indigo in fuming sulphuric acid, when largely diluted with water.

=INDIGO RED.= _Syn._ INDIGO RESIN, RED RESIN OF INDIGO. This is prepared by boiling alcohol (sp. gr. ·830), on powdered indigo previously exhausted by digestion in dilute acids and in a strong alkaline solution. When heated, it is converted into a white sublimate (deoxidised indigo red), but recovers its red colour by the action of nitric acid.

=INDIGO WHITE.= _Syn._ INDIGOGENE, INDICYLE, REDUCED INDIGO, HYDROGENISED I., HYDRATE OF I. Reduced or deoxidised indigo blue.

_Prep._ The yellow alkaline solution obtained by one or other of the processes noticed under INDIGOTIN is carefully protected from the air, both before and after precipitation with hydrochloric acid; and the precipitate, after being rapidly washed with recently boiled distilled water, or with very dilute sulphurous acid, is drained on a filter, dried in vacuo, and then at once transferred to a well-stoppered bottle.

_Prop., &c._ A greyish-white mass of minute crystals, generally light blue on the surface, and rapidly turning blue on exposure to the air; soluble in alkalies, alcohol, and ether, to which it imparts a yellow colour. These solutions deposit indigo blue on exposure to the air. A solution of this substance constitutes the indigo vat of the dyer (see _above_).

=INDIGO'TIN.= _Syn._ CERULIN, INDIGO BLUE. This is the pure blue principle of indigo. It appears to be the oxide of the same organic radical of which indigo white is probably the hydrate.

_Prep._ 1. Indigo (in fine powder) is digested successively in dilute hydrochloric acid, solution of potassa, and alcohol; the dried residuum is crude indigotin.

2. Indigo (in fine powder), 1 part; green sulphate of iron, 2 parts; hydrate of lime, 3 parts; water, 15 parts; mix, agitate occasionally until the colour is destroyed, then decant the clear portion, precipitate with dilute hydrochloric acid, and wash the powder first with water, and then with boiling alcohol, until the latter ceases to acquire a yellow colour.

3. Caustic soda and grape sugar, of each 1 part; water, 20 parts; powdered indigo, 5 parts; mix, and proceed as last. The above are essentially the same as the indigo vat, but on the small scale.

4. The process for estimating the value of indigo given under INDIGO is a good process for obtaining Indigotin.

_Obs._ The product from all the above exceeds 50% of the indigo operated on.

5. (Taylor.) Powdered indigo, 2 parts; plaster of Paris, 1 part; water, q. s. to reduce the mixture to a thin paste; spread the mass evenly upon an oblong iron plate to the depth of about 1/8 inch, and dry it by a gentle heat. It must then be held over the flame of a spirit lamp, when a disgusting odour will be evolved, the mass will begin to smoke, and in a few minutes will be covered with a heavy purple vapour, which will condense into brilliant flattened prisms or plates of an intense copper colour, forming a thick velvety coating over the surface immediately exposed to the heat. Should the mass catch fire, it may be instantly extinguished by a drop of water let fall upon it. _Prod._ 15 to 18%. See INDIGO, &c.

=INDIUM.= IN. = 113·4. This very rare metal was discovered by means of the spectroscope by Messrs Reich and Richter in a specimen of zinc-blende from Freiberg, in 1863. Since then it has been found in the flue dust of some zinc furnaces worked in the Hartz mountains, also in a black blende, known as christophite, occurring in Saxony; in the Wolfranc of Zinnwald, associated with zinc, as well as in Wolfranc alone; and also in the blende met within steatite, near Schlaggenwald. In all of these substances the indium is present in very minute quantity,[354] and is more or less associated with lead, arsenic, cadmium, iron, and copper; its separation from which is matter of no inconsiderable labour and difficulty.

[Footnote 354: In the flue dust of the zinc furnaces it is present to the amount of about 0·1 per cent.; in christophite in the proportion of 0·0062 per cent.]

The following process for the detection of indium in zinc-blende, and its extraction from the same source, is given by Winkler. Precipitate the hydrochloric acid solution of the roasted ore with metallic zinc at the boiling heat; dissolve the precipitate in nitro-hydrochloric acid; remove the arsenic, cadmium, &c., by sulphuretted hydrogen, and precipitate the indium as oxide by barium carbonate. Should this precipitate contain any iron, it must be removed by resolution, heating with sodium sulphate, and digestion with barium carbonate in a closed vessel. The indium may also be precipitated from the original solution, either directly by barium carbonate, or from a solution containing sulphuric acid, by neutralisation with sodium carbonate, till a precipitate begins to form, and addition of sodium acetate; it is then precipitated as a basic sulphate containing zinc."[355]

[Footnote 355: Various other processes are given in 'Watts' Dictionary.']

Indium may be obtained in the metallic state from the reduction of its oxide by means of hydrogen; charcoal or carbonaceous fluxes are not good reducing agents, as their employment necessitates a very high temperature, and loss from volatilisation occurs. Sodium is found to be the best reducing agent when large quantities of the metal are required.

Böttger's method is to precipitate the indium by zinc, to press the spongy metal so obtained in hot water, then to submit it to pressure in a screw press between filtering paper, and finally to melt it with cyanide of potassium.

_Prop._ Indium is a soft, white, durable metal, somewhat resembling cadmium, wholly destitute of crystalline structure. Its specific gravity, which is 7·421 at 16·8° C., is not altered by rolling or hammering. When heated in the air to 176° C., it melts without becoming oxidised; at a temperature above this, however, it becomes covered with a coating of suboxide, becoming gradually changed into the yellow sesquioxide. Indium is less volatile than either cadmium or zinc. It dissolves slowly in dilute sulphuric and hydrochloric acids, hydrogen being given off. In strong hydrochloric acid it dissolves rapidly. Nitric acid oxidises it, evolving at the same time nitric oxide; whilst sulphuric acid converts it into anhydrous sulphate.

When examined by means of the spectroscope, the flame of indium reveals two brilliant bands--a violet and a blue one.

Indium is completely precipitated from a solution of its acetate, as well as from neutral solutions of its salts in general, by sulphuretted hydrogen. Ammonia, neutral sodium carbonate, and acid sodium carbonate, throw down white precipitates insoluble in excess of the precipitant; caustic potash and soda produce a white precipitate of indium hydrate, soluble in excess. Barium carbonate precipitates it completely. Potassium ferrocyanide gives a white precipitate.

_Estim._ "The most convenient method of estimating indium is by precipitating it as hydrate with ammonia, dissolving the washed precipitate in hot dilute nitric acid, evaporating, igniting, and weighing the oxide thus obtained. Precipitation with sulphuretted hydrogen does not give exact results on account of the solubility of the indium sulphide."[356]

[Footnote 356: Watts.]

Indium forms compounds with bromine, chlorine, iodine, oxygen, and with several of the organic and inorganic acids.

=INDURA'TION.= In _pathology_, an increase in the consistence of any portion of the body, usually resulting from chronic inflammation, pressure, or friction.

=IN'FANCY.= "The domestic treatment of infants and children is comprised in the application of the laws of health to the mother as well as to the child. The position of parent is one of serious responsibility, both morally and physically, and the edict has gone forth that 'the sins of the parent shall be visited on the children.' If we could ensure good mothers, we could vastly improve the race of men. The nursing mother of a sick infant must, by following faithfully the rules of health in respect of the four great hygienic principles--food, clothing, exercise, and ablution--give health with her milk to her offspring; she must also pay close attention to her mind, avoid all sources of irritation and anxiety, and remember that an angry mother sours her milk, and produces a fractious and often a diseased infant. I am quite of opinion that if mothers were sound in constitution, and bestowed the requisite care upon the maintenance of their health, we should hear little of diseases of children. In children, as well as in parent, the rules of health must be carried out," and their neglect cannot fail to bring with it a heavy retribution. (Eras. Wilson.) See EXERCISE, NURSING, &c.

=INFANT DEATH-RATE.= In England, according to Dr Farr, out of 1000 infants born, 149 die annually before reaching their first year; and the same authority tells us that 311 out of every 1000 die during the first month in the same period. Amongst illegitimate children, the lives of one half never exceed the first month.

The above figures represent the yearly average of infantile deaths throughout the whole of England, when we come to the large cities the mortality is notably higher. In Liverpool, for instance, out of 1000 children born, 239 died in their first year.

When we examine into the infant mortality prevailing amongst different classes, we find the proportion existing between the death-rate of the children of the nobility, and the general death-rate up to one year, to be as 3 to 8.

In 1874, Mr Charles Ansell, jun., published a work entitled 'Statistics of Families of the Upper and Professional Classes,' in which he showed, from investigations into the deaths occurring amongst 48,000 children of the wealthy, professional, and titled classes, that in the first year of life, about 80 only of such children die out of every 1000. According to Dr Farr, the northern countries of Europe show a much lower infant death-rate than the southern ones. Infant mortality is lowest in Norway, and highest in High Bavaria, where 404 infants per 1000 die in their first year. In New York, in 1869, the mortality amongst infants under one year old was 27·4 per cent. and in 1873, 31·0 per cent.

Both in France and England the mortality prevailing amongst illegitimate children up to the age of one year is very large. In 1860, the death-rate amongst the foundlings of the Loire-Inférieure, was as much as 876 in the 1000, and it averages between 500 and 700 in France. In Wakefield, amongst the same class of children, it was 26·22 per cent.; in Coventry, 40; in Padstow, 50; and in Bantry, 80; in manufacturing towns the average is 35 per cent. In London the number of illegitimate children who die annually under the age of a year is probably about 75 per cent.[357]

[Footnote 357: 'Proceedings of the Obstetrical Society for 1870.']

In the Montreal Foundling Asylum, out of 4060 infants, only 7 per cent. lived one year. In the rural districts of England and also in Bavaria, the average of deaths at one year is about the same for the illegitimate as for the legitimate children.

In the 'Transactions of the Obstetrical Society for 1870' there is a valuable and interesting report, throwing much light on the condition and treatment of the children of the poor in England. The following is the substance of this report, the information contained in which was collected by various members of the society:--It was found that amongst the poorer populations of villages 30 to 90 per cent. are attended by midwives, and that this custom prevails to an almost equal extent in the large provincial and manufacturing towns. Thus in Glasgow, 75 per cent., in Coventry, 90 per cent.; and in Leeds and Sheffield, equally large numbers of the population employ the services of these women. In Edinburgh the midwife is rarely called on; neither is she in the West End of London; but in the East End 30 to 50 per cent. of the accouchements are undertaken by women.

Except in Glasgow, Sheffield, and London, the women are asserted to be totally ignorant and incompetent to meet any difficulty that might arise. In country districts the pernicious custom of giving an aperient to a newly born babe was very general, but less prevalent in London and the large towns. Amongst the married poor, suckling was found to be the rule; and it seemed to be pretty conclusively proved that it is often unreasonably prolonged for eighteen months or even two years, as a preventive to renewed pregnancy. It was found, however, that illegitimate children were rarely suckled, but almost always fed on artificial food. Amongst the married poor also it appears universal to give the children artificial food as well as the breast, and this from a very early and tender age. Further, it was found that the food was generally unsuited to the child both in quantity and quality. It consisted chiefly of bread soaked in water and milk, and sweetened, of arrow-root, sago and corn flour, and such like objectionable substances.

In one case the mother admitted to giving her infant (who was a few months old only) a diet similar to that she herself partook of, viz.--cheese, bread, meat, salt fish, heavy pastry, vegetables and beer. Amongst the upper classes it was ascertained that there is an increasing tendency amongst mothers to discontinue lactation, and to employ instead the services of a wet nurse; and where this was not done, it was found that the food partaken of by the babe was much more judiciously chosen than is the case amongst the poorer women. Mr Curquiven and others observed that a large number of women in London do not suckle their offspring, because of a deficient secretion of milk. It is satisfactory to find that both in the manufacturing and agricultural districts, the children of the poor are so constantly in the open air; but equally unsatisfactory to learn that at night they sleep in ill-ventilated and over crowded dormitories. The infant is encouraged to sleep to the utmost, and should it fail in securing renewed slumber (its waking being attributed to a desire for food), is very often dosed with gin, syrup of poppies, and paregoric. Another plan adopted for keeping infants quiet, consisted in letting them remain in the cradles and allowing them to suck the nipple attached to the empty feeding bottle, long after the food had been consumed; a practice that gives rise to infantile dyspepsia.

As regards cleanliness, it was learnt that poor people's children are tolerably well attended to in this respect, or rather that the baby generally comes in for a larger share of ablution than the elder ones, who are sometimes much neglected in the matter of soap and water. The clothing of the little ones was much too scanty, and this was the case no matter what the season of the year. A prevalent practice, except in the agricultural villages, was that of giving the children cordials, spirits, and medicines.

A still worse custom was found to be the systematic administration of opiates. At Long Sutton, in Lincolnshire, which has a population of 6000, one chemist alone sold 25-1/2 gallons yearly of Godfrey's cordial (a mixture principally consisting of treacle and opium), whilst 6-1/2 pints were got rid of weekly by another chemist in the same town. This administration of anodynes was mostly confined to illegitimate infants, and factory children placed out to nurse. A habit not unusual was that of an intentional deferring sending for a doctor when the child was first seized with illness, medical advice being only sought when in many cases it could be of no avail. Desertion by fathers and mothers of their children, especially of illegitimate ones, as well as concealment of birth and infanticide, were found to be much more general in London and the larger cities than in the country.

The causes of the high rate of infant mortality prevailing amongst the poor, seem very clearly indicated in the above abstract. For instance, the deaths of nearly half the children under one year of age are referable to diarrh[oe]a, convulsions, atrophy, mesenteric disease, and allied disorders; all of which maladies are caused by the grossly erroneous and unsuitable diet upon which the children are fed. In the article "Infants' Food," we have already pointed out that the proper and only safe aliment for an infant up to the age of eight or nine months is the maternal milk, and failing this, the pure and unadulterated milk of the cow; and we have furthermore shown that the admission into the dietary of infants even above nine months old, of farinaceous foods, should be regulated with great caution. Yet we learn from the above report, that in the early days of the infants' existence, amongst the poor the breast milk is in most cases supplemented by large quantities of these very farinaceous matters, which we have shown to be so prejudicial and dangerous. That the deaths from these causes are clearly preventable, in a large measure, if not wholly, is proved by the very much less extent in which they occur amongst the higher classes, who use much greater judgment in the selection of their children's food. Another important factor in the high infant death-rate is the extensive use of narcotics, a practice there is no doubt which yearly carries off a large number of infants, by poisoning, more or less prolonged. Inadequate clothing is likewise another source of mortality amongst the very young, whose tender frames easily succumb to inclement weather, and the sudden changes of temperature occurring in our variable climate. Hence we shall have no difficulty in understanding why pneumonia, bronchitis, &c., should be so prevalent among poor children. The habits of overcrowding and bad ventilation which prevail amongst the poor must also be fertile sources of disease amongst their offspring--the more immediate effect of such violations of sanitary principles resulting in bronchitis. That the extensive recourse by the poor to uneducated and unskilful midwives, also adds to infant mortality, seems indisputable.

In the report already alluded to, beyond reference to the fact that infanticide was rare, we find no mention made as to the number of violent deaths occurring amongst infants. It appears that about a sixteenth of the mortality amongst infants under one year old is due to violence, mostly accidental, the great majority of such deaths being caused by the mother lying upon and smothering her babe. These misadventures are said to occur mostly on Saturday nights, and raise the question as to whether a large proportion of such deaths are not due to the drunkenness of the mothers, who retire to rest in a state of alcoholic stupor.[358]

[Footnote 358: Blythe.]

The inference, we think, to be drawn from the above statements is, that the preponderating mortality prevailing amongst the children of the poor is due to ignorance and poverty, and not to intentional neglect or want of parental affection. Bearing in mind that poor women much more frequently suckle their babes than rich ones, it might perhaps be argued that this was evidence of greater maternal solicitude, and that, therefore, the poor mother exhibits more natural affection than the lady who consigns her offspring to the arms of the wet-nurse; but, possibly, were the circumstances of the two inverted, the lady might be found giving her infant the breast, whilst the humbler wife might call in the services of the wet-nurse; neither of them perhaps reflecting that, in choosing the latter alternative, they were depriving another little human unit of the maternal sustenance, and exposing it to the dangers of vicarious nurture and supervision. What these dangers are that beset the children of the poor when removed from their mother, the revelations of baby-farming and the appalling statistics of illegitimate infant mortality serve very forcibly to illustrate. For every 311 legitimate children of all classes 500 illegitimate out of every 1000 die each year under one month old, this large increase being due to cruel neglect and substitution of bad, insufficient, and improper food for the maternal milk. That in their own homes they are exposed to the serious hardships arising from errors in diet has already been shown, but in their own homes they die at little more than half this rate; hence the deduction is unavoidable that half of these poor little waifs perish because they are deprived of the care and solicitude of the mother.

Writing on this subject M. Hanon says that of 59,927 infants born in Paris, 20,049 are sent into the country to nurses. Of those children that remain in Paris, and that are so rarely suckled by their mothers, no less than 8250 die from 0-1 year, which gives a death-rate of 243 per 1000 births. As to the mortality of the unfortunate infants, 20,049 in number, sent off to nurse, this amounts to 500 or 700 per 1000 in the first year of life.

We extract the following from the 'Echo' of October 9th, 1878:

"ALLEGED BABY-FARMING.

"Dr Hardwicke, the coroner for Central Middlesex, held an inquest at the Islington Coroner's Court, Holloway Road, this morning, relative to the death of the female child of Emily Corley, a servant at 49, Gower Street, Euston Road. Mr Baby, the inspector under the Infants Life Protection Act, watched the case. The mother of the child had gone to service as a wet nurse after coming out of the workhouse, leaving it with one Ann Leach, who said it was a very delicate child. She added that she had for a time two children under one year of age with her, and had been told that this was contrary to the Act. The inspector under the Infant Life Protection Act pointed out that persons having more than one child to nurse under a year old had to obtain a licence. The coroner characterised the Act as a mere farce. It left children to take care of themselves after they were twelve months old--the most critical time of their existence. He also remarked on how prolific a source of prostitution such cases as the present were, where mothers had to forsake their own illegitimate offspring, depriving them of breast milk in order that they might sell it to the rich. The jury found that the child died from exhaustion following from diarrh[oe]a, accelerated by want of breast milk."

=INFANTS, Food for.= For the newly-born and very young of all mammiferous animals, no food is so expressly and admirably adapted as that drawn from the mother. In the nourishment of the babe from the maternal breast lies the soundest condition for its physical well-being and growth, subject to the qualification that the mother must be in good health, which, of course, implies that she must be well fed. This latter essential fulfilled, it is very wonderful to note how nature makes provision for the proper nourishment of the offspring by converting even a weakly and frequently ailing mother into a strong one during the period of suckling.

There may be, and doubtless are, many circumstances in which lactation cannot be practised with safety either to mother or child; but, where such circumstances do not exist, the practice of seeking the vicarious services of the wet-nurse, or of having recourse to other than the maternal milk, for many reasons, calls for remonstrance and reproof.

We may emphasise this by the following quotation from Dr West's admirable work, 'Diseases of Infancy and Childhood.' He says: "The infant whose mother refuses to perform towards it a mother's part, or who by accident, disease, or death is deprived of the food that nature destined for it, too often languishes and dies. Such children you may see with no fat to give plumpness to their limbs--no red particles in their blood to impart a healthy hue to the skin, their face wearing in infancy the lineaments of age; the voice a constant wail; their whole aspect an embodiment of woe. But give to such children the food that nature destined for them, and if the remedy do not come too late to save them, the mournful cry will cease, the face will assume a look of content, by degrees the features will disclose themselves, the limbs will grow round, the skin pure red and white."

But although the maternal aliment (or, failing this, that supplied from the breast of a young and healthy wet-nurse, who has been recently confined) is undoubtedly the best adapted for infantile nutrition, it fortunately happens that in circumstances where the infant is unable to be fed from either of these sources, we have a very valuable substitute in the milk of the cow, the similarity of which, in composition to woman's milk, will be seen at once by studying the following table arranged by Dr Letheby:

--------------+---------------------------+--------
| Woman's Milk. | Cow's
| | Milk.
--------------+--------+--------+---------+--------
| Max. | Min. | Average.| Average.
Casein | 4·36 | 2·97 | 3·52 | 3·64
Butter | 5·18 | 4·45 | 4·02 | 3·55
Sugar of Milk | 4·43 | 3·29 | 4·27 | 4·70
Various salts | 0·26 | 0·38 | 0·28 | 0·81
+--------+--------+---------+--------
Total solids | 14·20 | 11·09 | 12·09 | 12·70
Water | 85·80 | 88·91 | 87·91 | 87·30
+--------+--------+---------+--------
Total | 100·00 | 100·00 | 100·00 | 100·00
--------------+--------+--------+---------+--------

The milk of the cow being rather richer in solids than that of woman, it is considered desirable to somewhat dilute the former when it is used as food for the infant. Dr Letheby recommends the addition to it of a third of water, with a little sugar to sweeten it, and to render it more acceptable to the baby palate. It cannot be too forcibly insisted upon that immeasurably the best and safest food for an infant, next to human milk, is the milk of the cow, _and nothing else_, until it reaches the age of eight or nine months. It is perhaps needless to state that the milk must be perfectly pure and unadulterated, and that it will fail of being this if yielded by an unhealthy cow. The animal's food and habitat also exercise an important influence on the quality of the milk, that given by grass-fed cows roaming in open pastures undoubtedly being the best and richest.

Different cows yield different qualities of milk; hence, when milk from any particular cow suits an infant, it has been found desirable not to change it.

The newer and fresher the milk the better is it adapted for the child's use; that which has in the least become soured should be especially rejected.

Sometimes even fresh and good milk is found to disagree with a child. When this is the case it may be remedied by adding a little lime water to it previous to its being drunk. If it were practicable, and within the means of every family to keep their own cow, so that the infant could be fed with the milk directly it came from the animal, nature's example in giving it direct from the mother's breast might be followed. The writer remembers, some years ago, the Princess of Wales travelling with her baby on a voyage to and from Denmark, and being accompanied by her bovine purveyor in the shape of an Alderney.

In hot weather, more particularly, if milk be kept even for a short time it is liable to become acid, or "to turn," as it is called. It is, therefore, always desirable to keep it in a cool cellar till required for use, and in very hot weather it should be stood in ice.

The daily allowance of milk for a child during the first month of its life is two or three pints. M. Guillot says 2-1/2 lbs. avoirdupois is the least the babe can properly subsist on. He weighed several infants before and after they had taken the breast, and found that they had gained in weight, in quantities varying from 2 oz. to 5 oz.

Opinion is divided as to the value of condensed cows' milk as a food for infants. Its chief merit seems to be that it affords a substitute for the natural milk in cases where this latter is not obtainable, or where, in consequence of disease amongst the cows of a neighbourhood, it cannot with safety be consumed. Since the maternal fluid, without undergoing alteration or modification, forms so perfect and model a food for infants, it does not seem an unreasonable inference that the milk from the cow, which so nearly approaches it in composition and qualities, should prove most advantageous when partaken of under similar conditions. It has been asserted that condensed milk is inferior in strengthening qualities to the natural cows' milk. If this be the case it is certainly not due, according to Mr Wanklyn, to any removal of the constituents of the latter. In his useful little work on 'Milk Analysis' Mr Wanklyn says: "A year ago a report was spread that these preserved milks were preserved skim-milk, and not preserved new milk. I have myself examined the principal brands of preserved and condensed milk, which are in the London market, and find that the milk which has been condensed, or condensed and preserved, had been charged with its due proportion of fat."

The physiological facts that in an early stage of infancy the digestion is very feeble, and that until an infant has cut its first teeth there is but little, if any, secretion of saliva, which latter is essential for the conversion in the system of starch into sugar, point, therefore, to the imprudence of feeding very young infants upon so-called "infants' foods," where these consist of amylaceous substances. The starch of which these latter are composed not only fails to become assimilated, and therefore to produce no nutrient effect, but clogs up the lower parts of the bowels, and thus gives rise to a train of evils, amongst which may be included indigestion, diarrh[oe]a, vomiting, and not infrequently convulsions and death.

The difference in the mortality between infants under one year of age who annually die of convulsions in England and Scotland is attributed to the fact that whereas the English mother feeds her offspring on thick spoon-food, the Scotch woman nourishes hers from the breast. In 'The Fourteenth detailed Annual Report of the Registrar-General of Scotland' it is stated that "The English practice of stuffing their babes with spoon-meat occasioned the death by convulsions of 23,198 children under one year of age during the year 1868, out of 786,858 births; in other words, caused 1 death from convulsions in every 34 of the children born during the year in England. In Scotland, during the same year, only 312 infants under one year of age fell victims to convulsions out of 115,514 children born during the year; in other words, 1 death from convulsions in every 370 born during the year."

When a child has reached the age of eight or nine months the judicious use of farinaceous foods is not only unobjectionable but desirable; but even then it is most important to increase the quantity of the food very cautiously with the age, as well as to see that it has been well baked and afterwards boiled before being partaken of. In all cases it should be mixed with the milk.

When the child has reached the age of twenty months Dr Letheby advises the quantity of farinaceous food to be still further increased, and with a little egg given in the form of pudding until it attains its third year. At this period the child's diet may also include bread and butter, and at the end of it well-boiled potato with a little meat gravy.

From the third to the fifth year he prescribes a small quantity of meat, and at the end of the ninth year the usual food of the family. During all these periods the use of milk as an important article of the dietary is enforced.

The following table by the late Dr Edward Smith, exhibiting the proportions between the daily quantities of carbon and nitrogen required at different periods of human existence, illustrates the great preponderance of nitrogen demanded by the infant over those who succeed him in the scale of age:

Carbon. Nitrogen.
In infancy 69 6·72
At ten years of age 48 2·81
At sixteen years of age 30 2·16
At adult life 23 1·04
In middle life 25 1·13

See MILK.

=IN'FANTS' PRESER'VATIVE.= (Atkinson's.) Carbonate of magnesia, 6 dr.; white sugar, 2-1/2 oz.; oil of aniseed, 20 drops; compound spirit of ammonia and rectified spirit, of each 2-1/2 fl. dr.; laudanum, 1 fl. dr.; syrup of saffron, 1 oz.; caraway water, q. s. to make the whole measure 1 pint. Antacid, anodyne, and hypnotic.

=INFEC'TION.= _Syn._ CONTAGION. The communication of disease, either by personal contact with the sick or by means of effluvia arising from their bodies. Attempts have been made to restrict the term contagion to the former, and infection to the latter, but this distinction is now discarded by the majority of writers. The following are the principal diseases which are commonly regarded as contagious:--Chicken-pox, cholera, cow-pox, dysentery, erysipelas, glanders, gonorrh[oe]a, hooping-cough, hydrophobia, itch, measles, mumps, ophthalmia (purulent), plague, scald-head, scarlet fever, smallpox, syphilis, yaws. See DISINFECTANT, &c.

=INFLAM'MABLE AIR.= See HYDROGEN.

=INFLAMMA'TION.= _Syn._ INFLAMMATIO, L. In _pathology_, a certain state of disease. The common symptoms of inflammation are pain, swelling, heat, and redness, attended with fever, and general constitutional derangement when severe.

The treatment of inflammations, whether trifling; or serious, is essentially the same in principle, and only differs in degree. This consists in the adoption of the usual means for lowering the force of the circulation and the frequency of the pulse; of which leeching, purging, a low diet, and the use of refrigerant drinks and lotions, form the most important part. The constitutional derangement or symptomatic inflammatory fever, and inflammatory condition of the blood always accompany local inflammation, and progress with its intensity. In inflammations of a more purely local character, cupping or leeching the part immediately affected, or the parts adjacent to it, is in general more appropriate and successful. In these cases the application of refrigerant or sedative lotions, baths, &c., generally proves of much advantage. In cases in which there is induration or dryness of the part, the use of warm embrocations is indicated.

Inflammation often arises from apparently very trifling causes, particularly in persons of a full or bad habit of body, or who indulge in the free use of malt liquors. In some persons a very trifling local injury, as a slight abrasion, cut, prick, or sprain, produces a considerable amount of tumefaction, attended with severe constitutional excitement. Punctured wounds, sprains, and dislocations commonly furnish the most serious cases of inflammation that depend on mere external injury.[359] See ABSCESS, FEVER, TUMOUR, &c.

[Footnote 359: In all inflammatory cases of a serious nature, the reader is strongly advised to commit himself to the care of a medical practitioner.]

=Inflammation of the Bowels.= The common causes are incautious exposure to cold, the use of improper food, and the presence of acrid substances or hardened fæces in the bowels. The more constant symptoms are pain over the abdomen, thirst, heat, and extensive restlessness and anxiety; sickness, obstinate constipation, and a hard, small, quick pulse. In the later stages the pain and tenderness of the abdomen, especially around the navel, become excessive, and there is difficult micturition. In some cases the pain suddenly ceases, the belly becomes tumid, the pulse scarcely perceptible, the countenance ghastly, and the patient dies in a few hours. The treatment consists in blisters, leeches to the abdomen, hot bath and fomentations, aperient clysters, and mercurial purges; with effervescing draughts and opium to allay sickness, followed by diaphoretic salines and gentle aperients. See STOMACH AFFECTIONS, &c.

=INFLAMMATORY FE'VER.= See FEVER and INFLAMMATION.

=INFLUEN'ZA.= See CATARRH.

=INFU'SION.= _Syn._ INFUSUM, INFUSIO, L. A liquid medicine, prepared by macerating vegetable or animal substances in water, at any temperature below that of ebullition.

The mode of preparing infusions is, with most substances, precisely similar to that pursued for making the almost universal beverage--TEA. The ingredients are commonly placed in a stoneware pot or vessel (an 'infusion pot'), previously made hot; boiling water is then poured over them, and the cover being placed on, the whole is allowed to digest together, at first, for a short time, in a warm situation, as on the hob or the fender, and afterwards (the vessel being removed from the heat) until the whole becomes cold. The liquid is then poured from the ingredients, and the latter, being slightly pressed, if necessary, the infusion is strained through a piece of clean linen or a hair sieve for use. During the digestion the ingredients should be occasionally stirred, an important matter often neglected, and not even referred to by most pharmaceutical writers.

The substances employed for making infusions receive the same preliminary treatment as those intended for making DECOCTIONS. Shavings, leaves, and flowers require no previous preparation beyond being pulled asunder; but roots, woods, and other solid substances must be bruised or sliced, if in the green or recent state, or bruised or coarsely pulverised, if dry, for the purpose of exposing as large a surface as possible to the action of the menstruum.

The substances extracted by water from vegetables by infusion are chiefly gum, mucus extractive, tannin, certain vegetable acids, the bitter and narcotic principles, gum-resin, essential oil, and alkaloids. Some of these substances are only sparingly soluble in water at ordinary temperatures; but more readily so in hot water, and freely soluble in boiling water. The temperature of the water should be therefore proportioned to the nature of the vegetable matter operated on. For mere 'demulcent infusions,' in which starch and gum are the chief substances sought to be dissolved out, and when the active principle is scarcely soluble in water, unless at nearly the boiling temperature, boiling water alone should be employed; but when the medicinal virtues of vegetables are soluble in water at lower temperatures, it is better to employ hot water (165° to 175° Fahr.), and to allow a little longer period for the digestion. In many cases temperate water (from 60° to 70° Fahr.), or tepid water (from 80° to 90° Fahr.), may be used with advantage, especially in the preparation of 'aromatic bitter infusions,' and in most cases where it is wished that the product should contain as little inert matter as possible; but when water at low temperatures is employed, the period of the maceration must be proportionately increased. By adopting the method of maceration in vacuo, or in an atmosphere of carbonic acid, the menstruum may be allowed to lay in contact with the vegetable matter for an unlimited period, without decomposition taking place.

Infusions, like decoctions, are liable to undergo spontaneous decomposition by keeping, especially in warm weather, when a few hours are often sufficient for their passage into a state of active fermentation; they should, therefore, when possible, be prepared for use daily, as beyond twenty-four hours they cannot be depended on. The London College directs a pint only to be made at a time, thus very properly regarding them as extemporaneous preparations.

CONCENTRATED INFUSIONS, now so common in the shops, and, unfortunately, so generally used in dispensing, are either made by taking 8 times the quantity of the ingredients ordered in the pharmacop[oe]ia, and then proceeding in the usual manner, or by the method of displacement; or, by carefully and rapidly concentrating the simple infusions, by evaporation in a steam or salt-water bath, until reduced to about 1-7th of the original quantity. In either case the liquid is put into a strong bottle, without being filtered, and 10 to 12% of rectified spirit added to it, whilst still hot. The cork is then put in and secured down, and the whole agitated for some minutes, after which it is set aside for a week, when the clear portion is carefully decanted from the sediment for sale. Another method, which answers well with the aromatic bitter vegetables, is to take 8 times the usual quantity of the ingredients, and to exhaust them with a mixture of rectified spirits, 1 part, and distilled water, 3 parts; by digestion, or, better still, by percolation. Concentrated infusions made in this way keep well, and deposit scarcely any sediment. Many houses that are remarkable for the 'brilliancy' and beauty of these preparations, employ 1/3 spirit of wine and 2/3 water as the menstruum. It may, however, be taken, as a general rule, that for vegetable substances that abound in woody fibre, and contain little extractive matter soluble in water (as quassia, for instance), 1/6 to 1/5 part of spirit is sufficient for their preservation; whilst for those abounding in mucilage or fecula, or that readily soften and become pulpy and glutinous in weak spirit (as rhubarb), 1/5 to 1/3 is required.

By adopting the method originally suggested by Mr Alsop, infusions may be preserved, uninjured, for a year or longer, without the addition of spirit or any other substance. The only precaution necessary is to keep them in bottles, perfectly filled and hermetically sealed.[360] Our own plan is to put a few bruised cloves or seeds of black mustard into the bottles, which must be only 2-3rds filled, then completely fill them with a condensed atmosphere of carbonic acid gas; and, lastly, to stopper them and seal them over, so as to perfectly exclude the air. A pint of decoction of sarsaparilla and 1/2 pint of infusion of calumba, treated in this way, kept good for fully 9 years. By simply macerating in the infusion as much bruised mustard seed as can be added without flavouring the liquor, along with a little bruised cloves, we find that most vegetable infusions may be preserved in bottles which are occasionally uncorked, without either fermenting or becoming mouldy, by the use of very little spirit (1/9 or 1/10).

[Footnote 360: 'Pharm. Journ.,' i, 57.]

Before adding the spirit to infusions made with cold water, or with water which is only tepid, it is advisable to heat the liquid to about 185° Fahr., in a water bath, and after keeping it at that temperature for a few minutes, and allowing it again to become cold, to separate it from the precipitated matter, either by filtration or decantation.