THE ALUMNI JOURNAL. 



221 



/«/. Ergotcs, B. P., Made with Cold Water. 



Unch'g'd 



Mouldy 



ou 

 surface 

 but not 



sour 



Mould in 



creased 



The vapor ol formaldehyde was applied to 

 the infusions referred to in columns II and III 

 by passing a fine wire through the cork of the 

 bottle, and attaching to its extremity a tuft of 

 cotton wool moistened with either one or five 

 minims of formaldehyde solution, as the case 

 might be. Each bottle was open daily, and a 

 small quantity of the contents poured out. 



On contrasting columns II and III with the 

 corresponding ones IV and V, it will be noticed 

 that putrescence is either retarded or prevented 

 altogether by the antiseptic; but in the former 

 case, in which the vapor is employed, mouldi- 

 ness is either slight in amount or absent, whilst 

 in the latter, in which the antiseptic is added 

 directly to the infusion, the growth of mould is 

 very conspicuous and advances rapidly. This 

 confirms previous observations that bacteria 

 and pathogenic organisms succumb easily to 

 the influence of formaldehyde, and moulds are 

 very resistant to its inhibitory action. The use 

 of formalin vapor has the further advantage 

 that much less of the antiseptic actually remains 

 in the infusion, for at the end of a week the cot- 

 ton wool still retains a strong formaldehyde 

 odor. The vapor difi"used from the cotton wool 

 probably forms a thin film of liquid ou the sur- 

 face suflBciently charged with formaldehyde to 



prevent the growth of mould, whilst the infu- 

 sion beneath contains little or none. It is evi- 

 dent from the above table that i minim of for- 

 maldehyde solution on cotton wool suspended 

 above the liquid will preserve an infusion for 

 two or three days under the most adverse con- 

 ditions, and that 5 minims will keep it for a 

 week or more. Under more favorable circum- 

 stances, such as exist in most pharmacies, the 

 samples would have kept good for a much long- 

 er period. I regard the experiment with ergot 

 as a most severe test, for a cold aqueous infu- 

 sion of that drug is perhaps more easily putres- 

 cible than any other liquid with which the lab- 

 oratory operator has to deal. This use of for- 

 maldehyde in this manner as a preservative for 

 infusions appears to be quite free from objection. 

 The influence of formaldehyde on vegetable 

 colors is well illustrated in the following exper- 

 iment. Two samples of infusions of rose petals 

 were set aside, one containing -^ minim form- 

 aldehyde solution per fluid ounce, and the other 

 without any addition. After six weeks they 

 were examined. Both were covered with a 

 thick layer of mould. In the one containing 

 formaldehyde the color was unchanged; in the 

 other it had been completely destroyed by the 

 growth of fermentative bacteria. 



THE DISINFECTION OF BOOKS BY THE VAPOR OF 

 FORMALIN. 



Elmer Grant Horton has tested the efficiency 

 of formalin vapor as a disinfectant for books, 

 and as a result of his experiments has arrived 

 at the following conclusions: 



1. Books can be disinfected in a closed 

 space, simply by vapor of commercial formalin 

 by using i c. c. of formalin to 300 c. c. or less 

 of air. 



2. The vapor of formalin is rapid in its dis- 

 infectant action. The effect produced in the 

 first fifteen minutes is practically equivalent to 

 that observed after twenty- four hours. 



3. An increase in the amount of air to each 

 c. c. of formalin is not counter-balanced by an 

 increase in the length of time of exposure. 



4. In case the disinfection has been incom. 

 plete, the vitality of the organisms has been so 

 weakened that they survive only if transferred 

 in a few hours to media, suitable for their de- 

 velopment. 



5. The use of vapor of formalin is not detri- 

 mental as far as observed in any manner to the 

 books, nor is it objectionable to the operator 

 beyond a temporary irritation of the nose and 

 eyes, somewhat similar to that produced by 

 ammomsi.— Medical News, is 4- 



