236 



THE ALUMNI JOURNAL. 



REAGENTS AND REACTIONS KNOWN BY 

 THE NAHES OF THEIR AUTHORS.* 



BASED ON THE ORIGINAL COLLECTION BY A. 



SCHNEIDER, REVISED AND ENLARGED BY 



DR. JULIUS ALTSCHUL. 



Eleven years ago A. Schneider published in 

 the Phannaceutische Centralhalle a collection of 

 reagents and reactions known by the names of 

 their authors. This compilation was printed in 

 No. 35 of the year 1885 after it had been pub- 

 lished in somewhat abbreviated form in the 

 Phartnaceutischer Kalender for 1885, which ap- 

 peared in 1884. This first attempt at an alpha- 

 betical compilation of reagents and reactions 

 commonly and only semi-occasionally known 

 by the names of their authors met an undeniable 

 demand. The number of such reactions and 

 corresponding reagents, especially for qualita- 

 tive tests, is constantly growing. In the study 

 of chemical literature the reader frequently 

 loses the significance of a reference to such re- 

 agents or reactions because he is not familiar 

 with the name of the author, which stands for 

 the chemical synonym, or cannot readily find 

 the necessary literary reference. The following 

 list is to assist the reader in such emergencies. 

 That the original list filled a gap in chemical 

 literature was clearly demonstrated by the fact 

 that the edition of that number of the Central- 

 halle, although larger than usual, was rapidly 

 sold, and also by the numerous reprints. The 

 original list also led to the preparation of new 

 lists, of which might be mentioned the collec- 

 tion of Julien Delaite, Luettich, 1892; that of 

 Alberto Jan ssen, Florenz, 1894; of Dr. C. Duen- 

 nenberger, Zaerich, 1S94; and of Schneller, 

 Eichstaett, 1894. 



In none of these collections is any reference 

 made to the original list of Schneider. From a 

 note in Krauch's Priifung der chemischen Re- 

 agetitien. III. Auflage, p. 394, in which the 

 work of Dr. Dueunenberger and of Ferdinand 

 Jean et G. Mercier, Repertoire des reactifs spe- 

 ciaux, generalenient designee sous leurs noms 

 d'auteurs, Paris, 1896, is mentioned without a 

 reference to the collection of Schneider, it seems 

 apparent that the original has been forgotten. 

 The Pharmacetitische Centralhalle has therefore 

 seen fit to publish a revised list based on the 



♦Translated for the Pharmaceutical Review from the 

 original in Nos. 28 and 29 of the Pharmaceutische Cen_ 

 tralhalle, i8<)6. 



original one of 18S5, in which the more recent 

 literature is duly considered. The growth of 

 this literature is readily indicated by the fact 

 that the list published in 1885 contained about 

 200 articles (Dr. Duennenberger's list contains 

 350), whereas, the present list contains over 600 

 articles and cross references. The author does 

 not even now claim completeness for his list, 

 but hopes that in its new form it may prove a 

 serviceable adjunct both in study and labora- 

 tory practice. 



As far as the selection of material is concern- 

 ed, stress has been laid principally on qualita- 

 tive reactions. Quantitative tests have been 

 added only in so far as they serve also for qual- 

 itative determination. Most of the items belong 

 to the technical, pharmaceutical and physiolog- 

 ical branches of chemistry. Of bacteriological 

 reagents only a few of the most important were 

 added. 



The author has taken special pains to call at- 

 tention, by means of cross references, to rela- 

 tions existing between different reactions, and 

 particularly to the numerous modifications of 

 some of the more important reactions. An in- 

 dex is added to facilitate the use of the collec- 

 tion. 



Adamkiewicz' reaction for albumen. The 

 acetic acid solution of albumenous substances 

 is colored violet upon the addition of concen- 

 trated sulphuric acid, and possesses a greenish 

 fluorescence. The same reaction results if the 

 albumen is treated with a mixture of i vol. of 

 concentrated sulphuric acid and 2 vol. of glacial 

 acetic acid. The reaction is facilitated by the 

 application of heat, also, according to Wurster, 

 by the addition of a few grains of sodium 

 chloride. 



Agostini's reaction for glycose. If to 5 drops 

 of the urine to be examined 5 drops of Yz per 

 cent, gold chloride solution and 3 drops of 20 

 per cent, potassa solution are added, and the 

 mixture is gently heated, the presence of sugar 

 in the urine will be indicated by the formation 

 of a red color. 



Allen's reaction for vegetable fats. Equal 

 volumes of fat and nitric acid, specific gravity 

 1.4, are shaken for ^ minute and then set aside 

 for 15 minutes. The presence of vegetable fats 

 (cotton seed oil) is indicated by the formation 

 of a coflFee-brown color. 



Allen's reaction for phenol. With hydrochlor- 

 ic and nitric acids phenol produces a carmine 

 red color. 



Almen's reagent for blood. A liquid contain- 

 ing blood, when well shaken with a mixture of 



