ORGANIC ANTISEPTICS. 115 



cold process. For this purpose the ether is added in the pro- 

 portion of 10 per cent, to the liquid, and then, after the germs 

 have been killed, removed by the air-pump. The advantage of 

 this method over that of heat is that it has no effect on the 

 .albuminoids coagulable by the temperature of boiling water. 



Formaldehyde, also known as formol (formalin), will in the 

 near future enjoy extended employment as a powerful disinfectant. 

 Many objects, such as clothing dyed with delicate colours, furs, 

 &c., must not be disinfected with liquid antiseptics or by steam, 

 gaseous germicides alone being suitable. Among these there is 

 but little range of choice ; chlorine and sulphur dioxide not only 

 destroy the germs, but also the materials to which the latter 

 adhere ; and the only other resource at our disposal is in formalde- 

 hyde. The antiseptic properties of this substance were indicated 

 by 0. Low (I.) and by BUCHNER and SEGALL (I.), and have since 

 been thoroughly investigated by TRILLAT (I.). Meat-broth con- 

 taining one-twelfth part of formaldehyde per mil was found to be 

 perfectly free from germs at the end of several weeks. ARONSON 

 .(I.) found that typhus bacilli, StapJtylococcus pyogenes aureus, and 

 B. antliracis could not develop in bouillon containing one-twentieth 

 part per mil of this aldehyde. According to the researches of 

 J. STAHL (I.) and of E. VAN ERMENGEM and SUGG (I.), the spores 

 of B. anthracis and those (very tenacious of life) from garden soil 

 were killed by an exposure of one hour to the influence of a i per 

 mil solution of formaldehyde, and a solution containing i part 

 in 750 proved fatal to the germs in a quarter of an hour. This 

 disinfectant is therefore on a par with the strongest mineral 

 {bacterium) poison, corrosive sublimate, as regards efficiency, and 

 surpasses it in point of general applicability. Moreover, unlike 

 the mercury salt, formaldehyde is but slightly dangerous to man 

 and the higher animals. The air may be impregnated with suffi- 

 cient of the vapour for the purpose of disinfection, without causing 

 any greater inconvenience than coughing, which, however, soon 

 disappears, since one quickly gets acclimatised to this reagent. 

 Formaldehyde is generally met with in commerce as a 40 per cent, 

 .solution known as formalin. TRILLAT (II.) gives a few methods 

 for testing its strength and disinfecting value. A few pads of 

 cotton-wool or kieselguhr, &c., are moistened with the liquid 

 formalin and transferred to a box or other receptacle, wherein the 

 .articles to be disinfected (clothing) are suspended ; or the same 

 are laid between linen cloths moistened with the liquid. By this 

 means K. B. LEHMANN (I.) thoroughly disinfected a complete suit 

 of men's clothing, even when infested with anthrax bacilli, by 

 .the aid of 30 grams (a fraction over i oz.) of formalin in twenty- 

 four hours. For the preparation of formaldehyde on a small scale, 

 R. CAMBIER and A. BROCKET (I.) recommend a burner, and B. 

 TOLLEXS (I.) a lamp, both fed with methyl alcohol. In the 

 Jatter apparatus, a dome or cap of platinum gauze (2 c.m. high 



