Chapter II: BLEACHING of =Linen=:--Linen may be bleached in a similar way to (26)

Carbolic acid,
Tar acids,
Charcoal,
Great cold,
Heat sufficient to dry organic substances, but not to char them.

7. Preservative liquids and solutions. Many of these act by coagulating the albumen of organised bodies:

Antiseptics,
Alcohol,
Solutions of corrosive sublimate,
Solutions of common salt,
Solutions of saltpetre.

8. Destructive agents. Not true disinfectants, they act not by disinfection, but by destruction:

A dry heat of 200° to 400° F.,
The strong undiluted acids and alkalies.

9. Agents which act in many ways, partly by condensing gases, partly by absorbing moisture, and partly by a peculiar action on organic matter analogous to tannin:

Dry earths,
Clays,
The natural and artificial compounds of aluminium.

The table on the next page is a summary by the late Dr Letheby of some experiments made by Drs Dougall and Calvert, with the view of determining the relative powers possessed by certain substances of arresting putrefaction, as measured by their action in preventing the germination of animalcules and fungi, and the development of vaccine lymph.[258]

[Footnote 258: 'On the Relative Power of various Substances in Preventing the Germination of Animalculæ,' by John Dougall, 1871. Calvert, 'Proceedings of the Royal Society,' vol. xx, p. 185.]

=Disinfecting Compounds.= 1. (Sir WM. BURNETT'S DISINFECTING LIQUID.) A concentrated solution of chloride of zinc. See ZINC.

2. (COLLINS' DISINFECTING POWDER.) A mixture of dry chloride of lime, 2 parts, and burnt alum, 1 part. Used either dry or moistened with water. See LIME.

3. (CONDY'S DISINFECTING FLUIDS.) Solutions of the alkaline manganates and permanganates. Although this is an excellent and rapid deodoriser, and makes a most serviceable dressing for fetid sores, it must be borne in mind that it is in no sense an aërial disinfectant, its action being limited to the solid or liquid matters only with which it is brought into immediate contact. It exercises no corrosive action, but it is open to the objection that it leaves a brown stain upon linen. See MANGANESE.

4. (ELLERMAN'S DEODORISING FLUID.) This is said to consist chiefly of the perchlorides and chlorides of iron and manganese.

"In a report addressed to the Metropolitan Board of Works in 1859, Drs Hoffmann and Frankland stated that the perchloride of iron was the cheapest and most efficient deodoriser that could be applied to sewage." (Beasley.)

5. (LABARRAQUE'S DISINFECTING SOLUTION; LIQUOR SODÆ CHLORINATÆ, Ph. L. & D.) A solution of chlorinated soda, or, as it is commonly called, 'chloride of soda.' M. Labarraque made known this valuable disinfectant in 1822, and obtained the prize of the French 'Society for Encouraging National Industry' for its introduction.

6. (LEDOYEN'S DISINFECTING FLUID.) A solution of nitrate of lead, 1 part, in about 8 parts of water; or, of litharge, 13-1/2 oz., in nitric acid (sp. gr. 1·38), 12 oz., previously diluted with water, 6 pints. Sp. gr. 1·40.

7. (SIRET'S DISINFECTING COMPOUNDS.)--_a._ A mixture of sulphate of lime, 53 lbs., sulphate of iron, 40 lbs., sulphate of zinc, 7 lbs., and peat charcoal, 2 lbs., made into balls.

_b._ Sulphate of iron, 20 parts; sulphate of zinc, 10 parts; tan or waste oak-bark (in powder), 4 parts; tar and oil, of each 1 part; as before. Used for deodorising cesspools, &c.

8. (BISULPHIDE OF CARBON.) This generates, when burnt, sulphurous acid, and is, therefore, a very valuable disinfectant. Its highly inflammable nature, however, renders the adoption of certain precautions necessary in its use. A method of employing it in the form of fumigation will be found under the article "Fumigation."

9. Dry salicylic acid volatilised from a hot plate purifies the air, and perfectly disinfects the walls of a closed room. (VON HEYDEN.)

10. "SANITAS" is the name given by Mr Kingzett, its discoverer, to a new liquid antiseptic and disinfectant, containing peroxide of hydrogen and camphoric acid, and obtained by the atmospheric oxidation of turpentine. Sanitas is said by its inventor to possess the great advantages of being non-poisonous, and to exercise no injurious effects either on clothing or furniture. It is stated that its antiseptic power is distributed between the peroxide of hydrogen and camphoric acid, the peroxide of hydrogen being able to evolve large quantities of oxygen, which in this state is nascent, and of a powerful and oxidising character.

11. COOPER'S UNIVERSAL DISINFECTING POWDER. According to Professor Wanklyn this powder contains 70 per cent. of mixed chloride of sodium and chloride of calcium, and about 6 per cent. of anhydrous sulphate of zinc (equal to about 12 per cent. of hydrated sulphate), a little insoluble matter, and 15 per cent. of moisture.

12. DR BOND'S CUPRALUM AND FERRALUM. The first of these disinfectants is stated to be a mixture of the sulphates of copper and aluminium, with potassic dichromate and turpentine. Its inventor claims for it that it possesses great power of coagulating albumen and high value both as an antiseptic and deodorant. FERRALUM is a mixture of ferrous and aluminic sulphates, turpentine, and carbolic acid. Its chief use is for flushing sewers and in deodorising cesspools, urinals, &c.

13. BAYARD'S DISINFECTANT. A mixture of sulphate of iron, clay, lime, and coal tar.

_Summary of the Experiments made by_ DR J. DOUGALL,
_and by_ DR CRACE CALVERT, _on the action of various
Antiseptics on Protoplasmic and Fungus Life, and on
Vaccine Lymph._

KEY:
A - Quantity required to prevent Animalcules in six days.
B - Number of Days before Life appeared in a solution containing 1 of
substance in 500 water and 1/2 drachm of following--
C - Number of Days before Vibrio Life appeared in a solution of Albumen
containing 1 of substance in 1000 of solution.
D - Beef Juice.
E - Sol. of Egg Albumen.
F - Reaction of the Solution.
G - Infusion of Hay.
H - Human Urine.
I - Beef Juice and Egg Albumen.
J - Average of all.
K - Effect on Animalcules in Putrid Beef Juice and Egg Albumen, when
added in proportion in third column.
L - Animalcules.
M - Fungi.
N - Animalcules.
O - Fungi.
P - Effect of the Vapour or Gas during 24 hrs. on Vaccine Lymph.
Q - Animalcules.
R - Putrid Odour.
S - Fungi.
T - Mouldy Odour.

-------------------+---------------------------------------------------------------------------------------+-----------------------
| |EXPERIMENTS BY DR CRACE
| EXPERIMENTS MADE BY DR JOHN DOUGALL, OF GLASGOW. | CALVERT.
+--------+-------------------+------+-----------------------------------+-------+-------+-------+-------+-------
| | A | | B | | C
| |----+----+----+----+ +-----------------+--------+--------+ |-------+-------+-------+-------
| | | | | | | D | E | | | | |
| | | | | | |--------+--------+--------+--------+ | | | |
Substances used. | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T
-------------------+--------+----+----+----+----+------+--------+--------+--------+--------+-------+-------+-------+-------+-------
| |1 in|1 in|1 in|1 in| | | | | | | | | |
Acids. | | | | | | | | | | | | | | |
Mineral. | | | | | | | | | | | | | | |
Sulphurous | Acid. | 250| 50| 50| 117|Death.| 24 | 4 P. | 8 |Over 100|Killed.| 11 |Over 40| 21 |Over 40
Nitric | " | 400| 400| 200| 333| " | 18 | 4 P. | 15 | 5 T. | " | 10 | 50 | 10 | 23
Hydrochloric | " | 500| 400| 100| 333| " | 28 | 4 P. | 9 |Over 100| " | -- | -- | -- | --
Sulphuric | " | 800| 500| 100| 467| " |Over 100|Over 100| 30 | 10 T. | -- | 9 | -- | 9 | 11
Chromic | " |4000|1400|1200|2200| -- | 78 | 38 P. |Over 100|Over 100| -- | -- | -- | -- | --
Organic. | | | | | | | | | | | | | | |
Carbolic |Neutral.| 300| 300| 200| 267| None.| 12 | 50 T. | 38 | 36 P. | None. |Over 40|Over 40|Over 40|Over 40
Cresylic | " | -- | -- | -- | -- | " | -- | -- | -- | -- | " | " | " | " | "
Acetic | Acid. | 350| 25| 10| 125| -- | -- | -- | -- | -- |Killed.| 30 | -- | 9 | 50
Picric | " | 350| 350| 350| 350|Death.| 44 | 11 P. |Over 100| 44 P. | -- | 17 |Over 40| 19 |Over 40
Benzoic | " | 700| 700| 200| 533| " |Over 100|Over 100| " |Over 100| -- | -- | -- | -- | --
-------------------+--------+----+----+----+----+------+--------+--------+--------+--------+-------+-------+-------+-------+-------
Alkalies. | | | | | | | | | | | | | | |
Lime | Alk. | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | 13 | 19 |Over 40|Over 40
Potash | " | 300| 50| 10| 120|Death.| -- | -- | -- | -- | -- | 16 | -- | -- | --
Soda | " | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | 23 | 31 | 18 | 29
Ammonia | " | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | 24 | 50 | 20 |Over 40
-------------------+--------+----+----+----+----+------+--------+--------+--------+--------+-------+-------+-------+-------+-------
Haloids. | | | | | | | | | | | | | | |
Iodine tincture |Neutral.| 400| 400| 50| 283|Death.| 1 | 80 T.| 15 |Over 100| -- | -- | -- | -- | --
Chlorine gas | Acid. | -- | -- | -- | -- | -- | -- | -- | -- | -- |Killed.| 7 | 21 | 21 | --
Chloride lime | Alk. | 200| 200| 25| 142|Death.| 27 | 27 T.| 40 |Over 100| " | 7 | 18 | 16 | --
Chloride zinc | Acid. | 300| 300| 300| 300| " | 4 |Over 100| 18 | " | -- |Over 40|Over 40| 50 |Over 40
Chloride aluminum| " |2000| 500| 300| 933| -- | 19 | 4 P.|Over 100| 8 P. | -- | 10 | " | 21 | 50
-------------------+--------+----+----+----+----+------+--------+--------+--------+--------+-------+-------+-------+-------+-------
Sulphates, &c. | | | | | | | | | | | | | | |
Bisulphite lime | Acid. | 100| 50| 25| 58|Death.| 4 | 92 T.| 9 |Over 100| -- | 11 | 21 | 14 |Over 40
Sulphate zinc | " | 300| 300| 200| 267| " | 30 | 4 P.| 90 | 70 P. | -- | -- | -- | -- | --
Sulphate iron | " | 500| 500| 100| 367| ? | 14 | 5 T.| 35 | 40 T. | -- | 7 |Over 40| 15 | --
Common alum | " | 800| 500| 100| 467| -- | 14 | 3 P.| 38 | 15 T. | -- | -- | -- | -- | --
Sulphate copper | " |1000|1000| 800| 933|Death.| 86 | 20 P.|Over 100|Over 100| -- | -- | -- | -- | --
-------------------+--------+----+----+----+----+------+--------+--------+--------+--------+-------+-------+-------+-------+-------
Permanganate potash|Neutral.| 500| 200| 125| 275| None.| -- | -- | -- | -- | -- | 9 | 50 | 22 |Over 40
Alcohol | " | 350| 50| 20| 140|Death.| 4 | 4 T.| 10 |Over 100| -- | -- | -- | -- | --
Camphor | " | 300| 150| 50| 167| None.| -- | -- | -- | -- | None. | -- | -- | -- | --
Turpentine | " | -- | -- | -- | -- | -- | -- | -- | -- | -- | -- | 14 |Over 40| 42 |Over 40
-------------------+--------+----+----+----+----+------+--------+--------+--------+--------+-------+-------+-------+-------+-------

Note.--In the _first_ set of Dr John Dougall's experiments 3 drachms of a solution of the strength mentioned were treated with 1 drachm of a filtered infusion of hay, or with half a drachm of urine or half a drachm of the mixture of beef juice and egg-albumen. In the _second_ set of experiments equal parts of a putrid solution of beef juice and egg-albumen, full of living animalcules, and of the solution of the various substances of the strength known to be preventive of life (as in third column), were mixed together, and the results immediately noted. In the _third_ set of experiments 3-1/2 drachms of distilled water, containing 1 in 500 of the substances named, were treated with half a drachm of filtered beef juice, or half a drachm of a solution consisting of 1 part white of egg to 4 parts water. In the _last_ set of experiments, separate minims of vaccine lymph were exposed to the several vapours for 24 hours, and the dried spot in each case was moistened with glycerin and water, and sealed in a capillary tube until an opportunity for vaccination occurred, when the whole of the diluted lymph was used in one insertion so as to ensure its full effect.

In Dr Crace Calvert's experiments, 0·026 of a gramme of the substance was added to 26 grammes (1 to 1000) of a solution of albumen containing 1 part white of egg to 4 parts _pure_ distilled water.

The Animalcules observed were Monads (microphymes), Vibrios, and their cell segments (microerphymes), Bacteria (microzymes), Am[oe]ba, &c.; and the Fungi were Torula, Mycelium, Penicilium, &c., indicated in Table by letters T and P. Putrefaction was always characterised by a putrid odour, an alkaline reaction, and the presence of animalcules; whereas Mouldiness and Fermentation were distinguished by a mouldy or musty odour, an acid reaction, and the presence of Fungi.

14. LARMANDE'S ANTIMEPHETIC LIQUOR. A solution of the sulphates of zinc and copper.

15. THYMOL. From experiments made with this substance it appears to be a very powerful and valuable antiseptic, and likely, because of its non-poisonous and non-irritant qualities, to supplant carbolic acid in various branches of surgical practice, in which this latter agent has hitherto been employed; such, for example, as a dressing for wounds, ulcers, and as a topical application for certain skin eruptions, &c. Its difficult solubility and price (spite of its much greater antiseptic power), however, for the present at any rate, preclude it from being made available as an ordinary common disinfectant, as this term is generally understood. See THYMOL.

16. SILICATE OF SODA. It is stated that this salt has considerable anti-putrefactive powers.

17. Aluminised CHARCOAL. This is recommended by Dr Stenhouse as a cheap and very efficient decolorising agent. It is made by dissolving in water 54 parts of the sulphate of alumina of commerce in water, and mix it with 92-1/2 parts of finely powdered wood charcoal. When the charcoal is saturated it is evaporated to dryness, and heated to redness in covered Hessian crucibles till the water and acid are dissipated. The charcoal contains 7-1/2 per cent. of anhydrous alumina.

The natural disinfectants are air and water.

Air, when in violent motion, as is the case during a hurricane, has in many instances been known to arrest the course of certain epidemics; whilst in the form of ordinary ventilation, although inadequate alone to destroy the causes (whatever they may be) of contagion or infection, it is nevertheless found to supplement, to a considerable extent, the application of artificial and specific disinfectants. Hence the paramount necessity of perfect ventilation in all apartments in which the sick are placed, and hence also the measures taken in all hospitals to ensure by this means an increasing supply of fresh air to the wards in which the patients are lying.

The diminution in the amount of sickness prevailing in an army caused by the removal of the soldiers from barracks and placing them in sheds or under canvas is another illustration, tending to show the disinfectant properties possessed by an atmosphere in a state of circulation, when, of course, other hygienic precautions are not neglected.

In Hammond's 'Hygiène' for 1863 the author, who was surgeon-general in the United States army, says that he only met with one instance of hospital gangrene in a wooden pavilion hospital, and not a single one in a tent; and the same result is recorded by Kraus, of the Austrian army in 1859, who says he never discovered that gangrene originated in a tent; that, on the contrary, cases of gangrene at once began to improve when those suffering from the disease were sent from hospital wards into tents. In his work on 'Practical Hygiène' Dr Parkes advises all cases of typhus occurring in barracks, whenever practicable, to be sent to tents or wooden huts having badly-jointed walls.

The great solvent power of water, superadded to its being able to hold matters in suspension, renders it a most important disinfectant, and thus enables it in the form of rain to remove from the atmosphere many noxious and pestilential bodies that would doubtless, if allowed to increase, become a source of disease. The air-current which constitutes the ventilation of the House of Commons, before entering the Commons' chamber, is made to pass over a fine spray of water, by which means it has any dust or other organisms washed out of it. The beneficial effect of rain also in flushing drains and canals, and sweetening the superincumbent air, and of washing out of it many solid as well as gaseous objectionable impurities, is well known. The year 1860 was one of the wettest on record, as it was also one of the healthiest. Dr W. Budd recommends that when a room is to be disinfected, a short time before the process is commenced a tub of boiling water should be placed in the apartment, so that the steam may become condensed on the walls, and diffused throughout the air, as he believes there is a greater chance of ensuring the destruction of the disease germs by the aërial disinfectants than if these latter were allowed to act on the germs in the dry state.

We have already enforced in these pages the importance of the habit of personal cleanliness as being one of the greatest aids to the preservation of health; and although the unstinted use of soap and water will alone fail to effect the removal of any infectious or contagious maladies, their use will be found important auxiliaries in assisting recovery. But personal ablution is not the _sine quâ non_. The frequent cleansing of our dwellings, streets,[259] alleys (more particularly culs-de-sac), lanes, and the sheds and habitations of animals, by soap and water, or water alone, as well as the removal of all decaying or refuse materials from our midst, is of equal importance, and must not be disregarded, if we desire to make our sanitary surroundings such as they ought to be.

[Footnote 259: In streets where there is much traffic the air above has been found to contain large quantities of dust composed, amongst other matters, of the remains of horse droppings; hence the great importance of assiduously watering and cleansing the thoroughfares of all large cities and towns. A plan for laying the dust of streets has been suggested by Mr Cooper, and consists in watering them with waste chlorides of calcium and magnesium. Carbolic acid has been employed for the same purpose by many urban authorities for some years past.]

We extract the following from Dr Parkes' valuable and standard work--'Practical Hygiene,'

"_Disinfection of Various Diseases._

"EXANTHEMATA, SCARLET FEVER, AND ROTHËLN. The points to attack are the skin and throat. The skin should be rubbed from the very commencement of the rash until complete desquamation, with camphorated oil, or oil with a little weak carbolic acid. The throat should be washed with Condy's fluid, or weak solution of sulphurous acid.

"Clothes to be baked, or to be placed at once in boiling water, as directed further back. The clothes should not be washed at a common laundry. Chlorine or euchlorine should be diffused in the air, the saucer being put some little distance above the head of the patient. Carbolic acid and ether or carbolic-acid spray may be used instead.

"_Smallpox._--In this, as in all cases, there can be no use in employing aërial disinfectants, unless they are constantly in the air, so as to act on any particle of poison which may pass into the atmosphere.

"The skin and the discharges from the mouth, nose, and eyes are to be attacked. There is much greater difficulty with the skin, as inunction cannot be so well performed. By smearing with oil and a little carbolic acid and glycerin, or, in difficult cases, applying carbolised glycerin to the papules and commencing pustules, might be tried. The permanganate and sulphurious acid solutions should be used for the mouth, nose, and eyes. The clothing should always be baked before washing, if it can be done.

"The particles which pass into the air are enclosed in small dry pieces of pus and epithelial scales; and Bakewell, who has lately examined them, expresses great doubts whether any air purifier would touch them. Still it must be proper to use euchlorine or carbolic acid. Iodine has been recommended by Richardson and Hoffmann.

"_Measles._--Oily applications to the skin and air purifiers, and chlorides of zinc and aluminium in the vessels receiving the expectoration, appear to be the proper measures.

"_Typhus (Exanthematicus)._--Two measures seem sufficient to prevent the spread of typhus, viz. most complete ventilation and immediate disinfection and cleansing of clothes. But there is also more evidence of use from air purifiers than in the exanthemata. The nitrous acid fumes were tried very largely towards the close of last century and the beginning of this in the hulks and prisons where Spanish, French, and Russian prisoners of war were confined. At that time so rapidly did the disease spread in the confined spaces where so many men were kept, that the efficacy even of ventilation was doubted, though there can be no question that the amount of ventilation which was necessary was very much underrated. Both at Windsor and Sheerness the circumstances were most difficult. At the latter place (in 1785), in the hulk, 200 men, 150 of whom had typhus, were closely crowded together; 10 attendants and 24 men of the crew were attacked; 3 medical officers had died when the experiments commenced. After the fumigations one attendant only was attacked, and it appeared as if the disease in those already suffering became milder. In 1797 it was again tried with success, and many reports were made on the subject by army and naval surgeons. It was subsequently largely employed on the Continent, and everywhere seems to have been useful.

"These facts lead to the inference that the evolutions of nitrous acid should be practised in typhus-fever wards, proper precautions being taken to diffuse it equally through the room, and in a highly dilute form.

"Hydrochloric acid was employed for the same purpose by Guyton de Morveau in 1773, but it is doubtless much inferior to nitrous acid. Chlorine has also been employed, and apparently with good results.

"In typhus it would seem probable that the contagia pass off entirely by the skin, at least the effect of ventilation, and the way in which the agent coheres to the body linen seems to show this.

"The agent is not also enclosed in quantities of dry discharges and epidemics, as in the exanthemata, and is therefore less persistent and more easily destroyed than in those cases. Hence possibly the greater benefit of fumigations, and the reason of the arrest by ventilation. The clothes should be baked, steeped, and washed, as in the exanthemata.

"_Bubo Plague._ The measures would probably be the same as for typhus.

"_Enteric (typhoid fever)._ The bowels' discharges are believed to be the chief, if not the sole agents in spreading the disease; the effluvia from them escape into the air, and will adhere to walls and retain power for some time, or the discharges themselves may get into drinking-water. Every discharge should be at once mixed with a powerful chemical agent; of these, chloride and sulphate of zinc have been chiefly used, but sulphate of copper (which Dougall found so useful in stopping the growth of animalculæ), chloride of aluminium, or strong solution of ferrous sulphate (1 ounce to a pint of water), or carbolic acid. After complete mixing the stools must be thrown into sewers in towns; but this should never be done without previous complete disinfection. In country places they should be deeply buried at a place far removed from any water supply; they should never be thrown on to manure heaps or on to middens, nor into earth closets, if it can be possibly avoided. As the bedclothes and beds are so constantly soiled with the discharges, they should be baked, or, if this cannot be done, boiled immediately after removal with sulphate or chloride of zinc. It would be less necessary to employ air purifiers in this case than in others.

"_Cholera._ There can be little doubt that the discharges are here also the active media of the conveyance of the disease, and their complete disinfection is a matter of the highest importance. It is, however, so difficult to do this with the immense discharges of cholera, especially when there are many patients, that the evidence of the use of the plan in the last European epidemic is very disappointing.

"The ferrous sulphate (green vitriol), which has been strongly recommended by Pettenkofer as an addition to the cholera evacuations, was fully tried in 1866 at Frankfurt, Halle, Leipzig, in Germany, and at Pill, near Bristol, and in those cases without any good result. In other places, as at Baden, the benefit was doubtful. It seemed to answer better with Dr Budd and Mr Davies at Bristol; but other substances were also used, viz. chlorine gas in the rooms, and chloride of lime and Condy's fluid for the linen. On the whole it seems to have been a failure. Ferric sulphate, with or without potassium permanganate, has been recommended by Kühne instead of ferrous sulphate, but I am not aware of any evidence on the point. Carbolic acid was largely used in England in 1866, and appeared in some cases to be of use, as at Pill, near Bristol, and, perhaps, at Southampton. It failed at Erfurt, but, as it is believed the wells were contaminated by soakage, this is perhaps no certain case. Chloride of lime and lime were used at Stettin without any good result, and, on the whole, it may be said that the so-called disinfection of the discharges of cholera does not seem to have been attended with very marked results. At the same time it cannot be for a moment contended that the plan has had a fair trial, and we can easily believe that unless there is a full understanding on the part of both medical men and the public of what is to be accomplished by this system, and a conscientious carrying out of the plan to its minutest details, no safe opinions of its efficacy or otherwise can be arrived at. It would be desirable to try the effect of chromic acid or bichromate of potash.

"With regard to air purifiers little evidence exists. Chlorine gas diffused in the air was tried very largely in Austria and Hungary in 1832, but without any good results. Nitrous-acid gas was used in Malta in 1865, but apparently did not have any decided influences, although Ramon da Luna has asserted that it has a decided preservative effect, and that no one was attacked in Madrid who used fumigations of nitrous acid. But negative evidence of this kind is always doubtful. Charcoal in bulk appears to have no effect. Dr Sutherland saw a ship's crew severely attacked, although the ship was loaded with charcoal.

"Carbolic-acid vapour diffused in the atmosphere was largely used in 1866 in England; the liquid was sprinkled about with water, and sawdust moistened with it was laid on the floors and under the patients. The effect in preventing the spread of the disease was very uncertain.

"_Yellow Fever._ In this case the discharges, especially from the stomach, probably spread the disease, and disinfectants must be mixed with them.

"Fumigations of nitrous acid were employed by Ramon da Luna, and it is asserted that no agent was so effectual in arresting the spread of the disease.

"_Dysentery._ It is well known that dysentery, and especially the putrid dysentery, may spread through an hospital from the practice of the same close stool or latrines being used. As long ago as 1807, fumigations of chlorine were used by Mojon to destroy the emanations from the stools, and with the best effects. The chlorine was diffused in the air, and the stools were not disinfected; but this ought to be done as in enteric fever, and especially in the sloughing form. It is probable that carbolic acid in large quantity would be efficacious.

"With respect to _Erysipelas_, _Diphtheria_, _Syphilis_, _Gonorrh[oe]a_, _Glanders_, and _Farcy_, local applications are evidently required, and carbolic acid in various degrees of strength, and the metallic salts, are evidently the best measures.

"_Cattle Plague._ The experiments made by Mr Crookes on the disinfectant treatment of cattle plague with carbolic acid vapour have an important bearing on human disease. Although the observations fall short of demonstration there are grounds for thinking that when the air was kept constantly filled with carbolic acid vapour, the disease did not spread.

"So also euchlorine was employed in Lancashire by Professor Stone of Manchester, with apparent benefit. Dr Moffat employed ozone (developed by exposing phosphorus to the air), and he believes with benefit. As such experiments are very much more easily carried out on the diseases of animals than on those of men, it is much to be wished that the precise effect of the so-called disinfectants should be tested by continuing the experiments commenced by Mr Crookes, not only in cattle plague in the countries where it prevails, but in epizootic diseases generally.

"It may be said, in conclusion, that although positive evidence is so deficient, yet, taking into consideration the decidedly great and known effect of many so-called disinfectants, and air-purifiers on organic matters, and the fact that the infectious organic agencies are certainly easily destroyed in most cases (since free ventilation renders many of them inert, and few of them retain their power very long), it is highly probable that the specific poisons of the so-called zymotic diseases are destroyed by some of these chemical methods, and at any rate the careful and constant use of chemical agents for the destruction of the specific poisons in the excreta and discharges from the body, and when they pass into the air, is not only warranted, but should be considered comparative.

"_Purification of rooms after infectious diseases._ In addition to thorough cleansing of all woodwork with soft soap and water, to which a little carbolic acid has been added (1 pint of the common liquid to 3 or 4 gallons of water), and to removal and washing of all fabrics which can be removed, the brushing of the walls, the room should be fumigated for 3 hours with either the fumes of sulphurous or nitrous acids. Both of these are believed to be superior to chlorine, especially in smallpox. All doors and windows, and the chimney being closed, and curtains taken down, the sulphur is ignited as directed in our article FUMIGATION.

"In white-washed rooms the walls should be scraped, and then washed with hot lime to which carbolic acid is added.

"Mortuaries and dead-houses are best purified with nitrous acid."

These directions may be supplemented by the following:--The towels, sheets, articles of clothing, &c., should be boiled in water, or plunged in boiling water containing one to two handfuls of soda to the gallon, before being taken from the room, after which treatment they should be steeped in water containing 4 fluid ounces of carbolic acid to a gallon of water.

Fabrics soiled by the discharges, &c., such as rags, bandages, and dressings, if of little value should be immediately consigned to the flames; but if this be not convenient, they may be treated with carbolic acid and water, in the same manner as directed for towels, sheets, &c.

As soon as any infectious disease sets in, the room of the patient should be at once stripped of curtains, carpet, bed-curtains, valances, and all unnecessary garments, whether in a wardrobe or drawers, as well as of all superfluous furniture, especially chairs stuffed with wool or covered with fabric of any kind.

Disinfections of the apartment by fumigations must be postponed until it is vacated; as before such a time thorough disinfection is impossible.

Infected bedding, &c., should be removed in the boxes made for the purpose, and subjected to the heating process. In most towns provision is made by the Board of Guardians, and under the directions of the medical officer of health, for the disinfection process to be efficiently carried out. See DISINFECTING CHAMBERS.

The disinfection of articles of food is accomplished by thorough cooking, boiling in the case of milk, boiling and filtration in the case of water, and complete roasting, stewing, and frying of meat.

The experiments of Mr Crookes (to which reference has been made in the extract taken from Dr Parkes' 'Practical Hygiène') with carbolic acid during the cattle plague possess great practical interest both for the chemist and physiologist.

Of the use of carbolic acid as a disinfectant Mr Crookes, in the Appendix to the Report of the Cattle Plague Commissioners, writes as follows:

"According to the principles laid down, the air must be treated, and where there is no disease there is only a secondary use in treating anything besides the air. Several cowhouses have been treated with carbolic acid with very excellent results. The mode has been, first, to remove from the floor the mass of manure, which too often adheres to it; secondly, to sprinkle the floor with strong carbolic or cresylic acid; next, to wash the walls, beams, and rafters, and all that is visible in the cowhouse, with lime, in which is put some carbolic acid, 1 to 50 of the water used, or with strong carbolic acid alone. Next, to make a solution containing 1 of carbolic or cresylic acid to 100 of water, or, perhaps still better, 60 of water, and to water the yard and fold until the whole place smells strongly of the acid. Only a few farms have been treated in this way, so far as I know, but in each it has been successful. It may be well to give the cattle a little of the weak solution of carbolic acid, but this has not been so fully tried as the external use. The washing of the mouth and of the entire animal with the weak solution may be attended with good results, especially in the early stage of disease; but I know nothing of cure, and speak only hopefully of prevention.

"The animals seem to have an instinct for disinfection, and lick substances touched with this acid. They must not be allowed to drink it, as when strong it blisters the skin, and especially the mouth and tongue."

Mr Crookes also tried the effect of the acid by injecting it into the veins of the animals, and thus details the results of his experiments:--"It appeared evident that if harm were to follow the injection of carbolic acid, the mischievous effect would be immediate; but that if the fluid could pass through the heart without exerting its paralysing action on that organ, and could get into the circulation, no present ill effects need be anticipated. I therefore determined to push these experiments as far as possible, increasing the quantity of carbolic acid, until it produced a fatal result.

The next operation was on cow No. 11, in which 3 oz. of solution (containing 52-1/2 gr. of pure carbolic acid) were very slowly injected; no bad effect followed. Increasing the dose, cow No. 12 had injected into her vein 4-1/2 oz. of solution (equal to 78-3/4 gr. of carbolic acid); this also was followed by no immediate ill effect. Cow No. 13 was then treated with 6 oz. of solution (containing 105 gr. of pure carbolic acid), in two portions of 3 oz. each, five minutes' interval elapsing between each injection. The first 3 oz. produced a slight trembling, but not so severe as in the case of cow No. 10, as she seemed better in a few minutes. The second dose of 3 oz. was injected. This proved too much, or was pumped in too hurriedly, for almost before I had finished the animal trembled violently, its eyes projected, its breathing became laborious, it fell down and expired. The result could scarcely be attributed to the accidental injection of air into the vein, for the distress began with the injection of the first syringeful, and was only increased by the second; nor is it likely that this accident would happen twice consecutively. I was particularly careful on this point, and the construction of the instrument rendered such an occurrence scarcely possible with ordinary precaution. It is probable that the injection was performed too rapidly, or that the vital powers were lower than usual. In the case of the remaining animal, No. 14, I decided to inject as large a dose as it would bear, stopping the operation at the first sign of trembling, and delivering the liquid very gradually. The first syringeful caused no bad symptoms, and I had just finished injecting the second dose when trembling commenced. It was rather violent for a short time, but soon went off, and in five minutes the animal appeared as well as before.

This cow, therefore, bore without inconvenience the injection of 6 oz. of a 4 per cent. solution, containing 105 gr. of pure carbolic acid. Careful observations with the thermometer were taken before each operation. There were no more diseased beasts on the farm, or I should have carried my experiments still further. On visiting the farm the next day I was told that all the animals seemed better, and on testing them with the thermometer that statement was confirmed. I gave directions that each animal was to be drenched with half a wine-glassful (1 oz.) of carbolic acid in a quart of warm water every morning, but in other respects they might be treated as Mr Tomlinson, a skilful cow doctor, should direct.

"Business now calling me to London, I was unable to watch the further progress of these cases.

"This is to be regretted, as a series of daily thermometric observations would have been of great value in suggesting further experiments. I had, however, frequent accounts sent me. Cow No. 14 continued to improve slowly until convalescent; she is now quite well. Nos. 10, 11, and 12 remained apparently in the same state for four days; they then changed for the worse, and died. It is not improbable that had I been able to inject a further quantity of carbolic acid during the four days in which they were thus hovering between recovery and relapse, it would have turned the scale, and some of them at all events would be now alive and well.

The following table gives the thermometric observations;--

_Table showing the results of injecting carbolic acid
into the blood of animals suffering from the cattle
plague._

+-----+------------+-------------+---------+--------+-----------+
| | Grains of | Temperature | | | |
| No. | Carbolic | before | Second | Third | |
| | Acid | Injection | Day. | Day. | |
| | Injected. | | | | |
+-----+------------+-------------+---------+--------+-----------+
| | | F. | F. | | |
| 10 | 26-1/2 | 105·4 | 103·8 | Better.| Died on |
| | | | | | 6th day. |
| 11 | 52-1/2 | 103·8 | 102·8 | " | Died on |
| | | | | | 6th day. |
| 12 | 78-3/4 | 104·8 | 104·4 | " | Died on |
| | | | | | 6th day. |
| 14 | 105 | 103·7 | 103·1 | " | Recovered.|
+-----+------------+-------------+---------+--------+-----------+

If future experiments prove that injection of carbolic acid or other antiseptic will do good, it is an operation very easily performed. I have injected five animals, and taken thermometric observations within an hour. Sulphite or bisulphite of soda apparently occasions some pain, as the animals struggle very much; with carbolic acid I found them tolerably quiet. I have calculated the proportion which the carbolic acid bore to the whole quantity of blood in these operations. Taking the whole amount of blood in the animal at 150 lbs., there were injected into--

No. 10, 1 part of carb. acid, in 40,000 of blood.
" 11, " " 20,000 "
" 12, " " 13,300 "
" 14, " " 10,000 "

It is worth mentioning incidentally, that in the case of cow No. 14 (which recovered) the proportion of carbolic acid injected into the blood would have been enough to keep from decomposition the whole quantity of that liquid for a considerable time. In Nos. 10, 11, and 12 the proportion of carbolic acid would probably not have been sufficient for that purpose. I am informed by Dr Calvert that cresylic acid has much less coagulating power on albumen than carbolic acid, and my own experiments entirely confirm this statement."

We have described under "CHARCOAL" the disinfecting properties of that substance. These properties have been turned to excellent account by Dr Stenhouse, who has invented a charcoal respirator, which, causing the wearer to breathe air drawn through a layer of that substance, and by thus depriving the air so inspired of any noxious gases or exhalations, if present, becomes, if worn in an infected atmosphere, a great safeguard against disease. Dr Letheby was accustomed to use a charcoal respirator when analysing dead bodies and other putrid matters of suspected poisoning, and by so doing never experienced any ill effects, nor was he conscious of the offensive odour which but for its adoption he must have encountered.

Professor Tyndall has suggested for the same purpose a respirator of cotton wool, by means of which the air, being filtered before it enters the lungs, becomes deprived of minute particles of various substances suspended in it, as well as of the germs, which so many pathologists believe to be always present during the prevalence of epidemic maladies, and the cause, when inhaled, of the maladies themselves.

=DISINFECTING CHAMBERS.= The sanitary authorities of most large cities have made provision for the purification of mattresses, linen, wearing apparel, &c., by means of disinfecting chambers or ovens, in which receptacles the infected articles are subjected for a certain time to hot air. The simplest form of apparatus for this purpose, and one that could be used on an emergency, provided the articles to be disinfected were not too bulky, is a baker's oven. The drying closet of a good laundry would be so far unsafe, because it would occasionally fail to give a heat sufficient for the destruction of the noxious principles.

The disinfecting chambers employed in Liverpool are arched ovens of solid brickwork, having a depth of 7 feet from front to back, a width of 5 feet from side to side, and a height of 6-1/2 feet from the floor to the crown of the arch. The doors are made of wrought iron, tightly fitting into cast-iron framework. The floors are made of double iron gratings, having alternate openings, so arranged as to admit at pleasure hot air into the chamber. At the top of the arch there is an opening fitted with an iron valve, by which the air of the chamber escapes into an exhausting shaft which is connected with the chimney. The heating is accomplished by means of a cast-iron cockle, the smoke from which escapes by two cast-iron smoke flues, which, after forming a coil for the purpose of affording as great a heating surface as possible, pass along the hot-air passage under the chamber, into a chimney situated at the opposite end.

The cold air is drawn into a brick flue placed underneath the floor of the stokehole into a cavity on each side of the cockle, and thence into a space underneath the chamber, whence it becomes heated by the radiation from the surface of the two cast iron flues. From this cavity or passage it is conveyed at will through the gratings as already described. At the entrance of the cold air flue there is a damper, by which the temperature of the air may be regulated. A heat equal to 280° F. has been registered in this chamber, and as high as 380° in a drying closet over the cockle. Dr French, the medical officer of health for Liverpool, says "that, if necessary, a temperature reaching 500° F. can be attained in these chambers; but this temperature is of course never employed. Experience has proved that from 220° to 250° F. is the most suitable. Instances have been known where fabrics, after being exposed for some length of time to a temperature above 212° F., have sustained injury from being scorched.

In some of the chambers, carbolic acid powder is sprinkled on the floor.

We have taken the liberty of transcribing the following description and plates illustrative of the disinfecting stove used in the Royal Victoria Yard, Deptford, from that very useful publication, 'Chemistry, Theoretical, Practical, and Analytical,' published by Mr W. Mackenzie.

"This stove consists of a brick chamber with a slightly arched roof, and an iron movable floor in two pieces. The chamber is 7 feet deep, 6 feet 9 inches wide, and 5 feet 8-1/2 inches high in the centre of the arch. It is heated by a flue below the iron floor passing round 3 sides of the chamber and up a chimney. There is an opening in the upper part of the chamber in its centre, which passes along in the roof to the side, from thence down in the wall entering beneath the fire; this carries away any of the foul air of the clothes from the chamber through the fire and up the flue. This proceeding takes place after the clothes have been in the chamber say an hour and a half in the following manner:--The damper in the foul air shaft is withdrawn, and the furnace door is shut; any draught that gets to the fire comes to the chamber. Over the opening into the furnace is a square opening, fitted with a glass, inside of which is a fixed thermometer. When this shows a temperature of 200° F., the interior of the chamber is at 250° F., the highest point at which it is allowed to be. In the interior of the chamber at the sides there are little movable cranes, three rows of three supporting rods of iron on which wooden trays rest, and on which the clothes are placed when the iron cart is not used. The cranes move fore and aft to be out of the way when the cart is used. The cart is of iron on wheels, and runs into the chamber on tramways to keep it in position; in the interior of the cart are three iron trays for laying the clothes on. The lowest tray is always the hottest, so that it is prudent to use the cart, the iron bottom of which prevents burning. The iron ends of the cart are removed when it is placed in the chamber; so is the handle. It is usual to keep the clothes at the temperature of 250° F. for two hours.

There is a trap door 8 inches square about 14 inches above the upper edge of the furnace, and on a level with the iron floor of the chamber, for disinfectants. Carbolic acid and sulphur are used; the former is placed on a flat plate, the latter is sprinkled over the floor. These are used as the last, and after that has been the clothes are fit to be used without danger to any one.

_Elevation plan_ (fig. 5) shows the front of the chamber with the doors closed; the openings (Nos. 1, 2, and 3) are for inserting the long thermometer, which is pushed into the clothing to be disinfected; they correspond with the three trays. The thermometer can be withdrawn and examined without allowing much cold air to enter; plugs fit into these three openings when not used for the thermometer.

_Section._--The chamber is shown about the centre of its depth; the foul-air shaft (B) passes along the roof down the side wall, and beneath the fire (C); the opening where the fixed thermometer is placed is marked with dotted lines. The damper for the foul-air shaft (E) is represented as shut, and the damper for the chimney (F) is also shut.

_The ground plan_ shows the flue beneath the iron plates, which form the floor of the chamber, the dotted lines showing the foul-air flue (B), as it passes beneath the fire. In the flue (C) there are openings at D, D, D, for the purpose of cleaning it.

Another form of disinfecting chamber is that invented by Dr Esse, of Berlin, and employed in that city. The apparatus consists of two iron cylinders, one fitted within the other, with a space between, into which steam under pressure is introduced. The outer cylinder is surrounded with wood and the top with felt, to prevent the escape of heat. The articles to be disinfected are put in at the top of the inner cylinder, the inside of which soon becomes heated up by the surrounding steam. A pulley is used to lift the lid of the inner cylinder, around which the clothes are hung on pegs, not being allowed to touch the side of the cylinder. At the top of the inside cylinder is a brass box pierced with holes at the bottom, which dips a little way down, through which the air from the interior can rise. In this box the bulb of a thermometer being placed, the temperature of the inner chamber can be registered.

When the steam condenses in the space between the cylinders it is carried off by means of a valve, which is lifted when the water reaches a certain point in the condenser. In an hour's time the temperature of the interior cylinder can be raised to 235° Fahr.

For heating mattresses another apparatus has been devised by Dr Esse. It consists of an iron case with a spiral steam pipe in the centre, the steam inside the pipe being compressed to two atmospheres.

Dr Ransome has invented, for the use of the Nottingham hospital, a gas stove in the form of an iron box, well packed with a non-conducting material, which surrounds the outside. A channel leads to the interior of the box, and inside this channel gas is kept burning in such a manner by a modification of Kemp's regulator, that the temperature of the box shall range day and night between 235° and 255° Fahr.

An apparatus put to great use by the Holborn District Board during the epidemic of smallpox in 1871 was one made by Fraser's patent. Mr Fraser's disinfecting chamber consists of an oven or receptacle made of brick, with doors in front. Situated on the lower portion of this chamber is a covered furnace connected with flues, by means of which the interior space is heated to the desired temperature. By a particular arrangement the air laden with the noxious vapours given off by the tainted clothing is conveyed into the furnace, and so consumed. Belonging to the apparatus is a covered truck or cart, fitted with doors and dampers, and provided inside with racks and shelves for holding the materials to be purified, which are thus brought from the infected dwelling and placed, truck and all, inside the chamber. The infected materials, as well as the truck containing them, are then heated to the necessary point, disinfection being assisted by sulphurous acid gas, or some other material adapted for the purpose. When the process is finished the carriage with its contents is drawn back to the house from which they were originally taken, and the purified articles are restored to the owners. It will be seen that by this arrangement the vehicle is disinfected as well as the clothes it contains.

=DISLOCA'TION.= _Syn._ LUXATION; DISLOCATIO, L. The forcible displacement of a bone from its socket, either by violence or disease. The latter happens when the textures forming the joint have been destroyed by some independent organic affection. "A considerable share of anatomical knowledge is required to detect the nature of these accidents; and it is much to be lamented that students neglect to inform themselves sufficiently on the subject." (Sir A. Cooper.) In common cases the bones may be frequently replaced by forcibly extending the limb. This should be done as early as possible, and before inflammation sets in. The latter should be combated by aperients, local bleeding, refrigerant lotions, &c. Dislocations frequently exist without the fact being suspected, the swelling and inflammation being referred to other causes.

=DISPLACE'MENT.= See PERCOLATION.