558 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



tion of basements, vaults and sick rooms. In this he agrees with 

 the distinguished chemist, Prof. Blaney, of Rush Medical College, 

 who, in a recent letter to Mr. E. H. Sargent, the manufacturer, 

 writes as follows : " There is abundant scientific authority — with 

 which my own experienje accords — to prove beyond doubt the 

 immense value of this agent as a deodorizer, and, in a high degree* 

 as a disinfectant. While it is equally as prompt and efficient as 

 chloride of lime, the best known and the longest used of the 

 deodorizers, it has over it the 2:reat advantao;e that it has no offen- 

 sive odor of its own when neutral, and may be freely used about 

 the persons and clothing of the most sensitive persons without 

 excitii^g any feeling of disgust. As a deodorizer, for use in closed 

 apartments, and Avithin dwellings for general family use, I am of 

 the opinion that the chloride of zinc is the most safe, the most 

 prompt and the most efficient of the deodorizers now furnished for 

 general distribution." 



POTEXT DlSINFECT.ysT. 



The Dublin Medical Press states that Dr. Dewar, of Kirkcaldy, 

 has discovered that " for the disinfection of inanimate material the 

 addition of a little nitre to sulphur, and the combination of these 

 fumes with the steam of boiling water, improvises a disinfectant 

 at once the most powerful, most searching and most efficacious 

 w^hicli can be obtained, utterly destructive at once of any latent 

 contagion, and of every form of insect life." 



CoLLObiox. 

 By John P. Maynard, M. D. — Take two parts of sulph. acid, 

 sp. gr. 1.850, and one part nitric acid, sp. gr. 1.450. Mix them — 

 allow the temperature to fall to about 100 deg. Fahrenheit. Add 

 to this raw cotton, to point of saturation. Let it soak aliout one 

 to two hours. Pour off the acids. Wash the cotton till litmus 

 paper shows all acidity removed. Dry thoroughly. The cotton 

 will now be foundto be converted into a gum, completely soluble 

 in ether, of about .750 sp. gr., or in pure ether three parts and 

 alcohol ninety-five percent, one part. About two ounces of cotton 

 thus prepared will make about one pint of collodion of proper 

 consistency for surgical purposes. For photographic objects, a 

 less amount will be sufficient. The conditions for success for this 

 formula are simply precision in the details and careful manipula- 

 tion, which a little experience will perfect. 



