274 



IHE ALUMNI JOURNAL. 



which is employed in the powder form as 

 an antiseptic in surgery. Formaldehyde 

 is being constantly given off by this com- 

 pound when in contact with an open 

 wound, acting as an antiseptic and facili- 

 tating the healing process. 



The sterilizing action of formaldehyde 

 has led to its application to the preserva- 

 tion of food products. In 1892 Trillet, a 

 French chemist, patented its use in this 

 particular. He stated that a meat extract 

 with the addition of j-s^ou part of formal- 

 dehyde, can be indefinitely preserved. It 

 has been recommended to chemists as an 

 addition to milk which cannot be sub- 

 jected to analysis at once. Serious ob- 

 jections have been made since this time 

 against its use as a food preservative. 



Formalin in 4 per cent, (aldehyde) so- 

 lution, is a valuable agent for preserving 

 and hardening anatomical specimens, 

 there being no shrinkage ; it can also be 

 employed for preparing microscopical 

 sections of animal as well as vegetable 

 tissues. The specimens of animal tissues 

 retaining their original color in every 

 case, while vegetable preparations show 

 no change in their chlorophyl. 



Among the various tests for formalde- 

 hyde we have : 



1. Ammoniacal silver nitrate solution 

 is at once reduced. 



2. Fuchsine sulphurous acid is red- 

 dened. 



3. Very dilute aqueous solutions of 

 aniline give a white precipitate of formal- 

 dehyde-aniline. 



4. A solution of a hydroxylamine salt 

 when boiled wath formaldehyde yields an 

 oxime (CH2=N0H) which, when further 

 heated, yields hydrocyanic acid — known 

 by its odor. 



5. Addition of bromine water to an 

 ammoniacal solution of formaldehyde 

 gives rise to a white precipitate of hexa- 

 methylene-teltamine-bromide. 



For quantitative estimation Klar rec- 



ommends the following; In a flask of 

 250 cc. capacity (glass stoppered), 60 cc. 

 of ^ ammonia solution, and 5 cc. of the 

 formaldehyde are shaken together and 

 set aside for three to four hours : again 

 shake, to cause absorbtion of all gaseous 

 ammonia, add quickly, 20 cc. of y hydro- 

 chloric acid and water sufiicient to make 

 up to 250 cc. In 25 cc. of this sample 

 the excess of normal acid is estimated by 

 titrating back with normal sodium hy- 

 drate solution, using rosolic as indicator, 

 six molecules of formaldehyde uniting 

 with 4 molecules of ammonia. 



BOTANY AND MATERIA MEDICA. 



By Prof. H. H. Rusby. 



The Herbarium of the New York College of Pharmacy 



Mr. P. A. Rydberg makes numerous 

 acknowledgements in his monograph 

 upon the North American species of 

 Physalis and related geneca for assistance 

 derived from our college herbarium. Of 

 two of the new species described, one ex- 

 ists in but two, the other in but three, 

 other collections in the country. 



Among several new species of Saxi- 

 fraga described by Mr. J. K. Small in 

 the current number of the Bulleti7i of the 

 Torry Botanical Club, one is based upon 

 a specimen seen only in this herbarium. 

 Several other monographs now in course 

 of preparation in this country and Europe 

 have also drawn freely for information 

 upon the same source. 



REVIEWS. 



The North American Species of 

 Physalis and Related Genera. By 

 Per Axel Rydberg, Memoirs of the Tor- 

 rey Botanical Club, IV. 5. pp. 76, with 

 index. 



All our readers are probably familiar 

 with the little plant known as "Ground 

 Cherry" and "Ground Apple," and the 

 delicious fruit which it yields; but none 



