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C. U. C. p. ALUMNI JOURNAL 



fection of rooms with formaldehyde, or 

 by means of Salforkose, a preparation 

 containing formaldehyde and carlDon 

 disulphide. The process is essentially as 

 follows: A mixture of ammonia and 

 menthone or an essential oil containing 

 menthone, such as dementholized Jap- 

 anese oil of peppermint, is vaporized 

 within the room which has been subject 

 to the disinfection. It is claimed that 

 the room can be used sooner than if 

 ammonia alone be employed. 



Mimeograph Inks. 



The following processes for manu- 

 facture of mimeograph inks are subject 

 to U. S. Patents : 



( 1 ) A carbon black pigment is ground 

 thoroughly in a suitable mineral oil, with 

 or without the addition of a small quan- 

 tity of blue pigment. This mixture is 

 then incorporated with Turkey-red oil, 

 or other sulphonated oil. 



(2) A colored pigment or lake color 

 is employed in place of the black pig- 

 ment in I. 



(3) A dyestufif possessing the desired 

 color, or its basic substance is dissolved 

 in alcohol. An acid which is capable of 

 forming colors soluble in oils, and a 

 small quantity of a solvent for aniline 

 dyestufTs (basic) are added. This solu- 

 tion is thoroughly ground with a mineral 

 oil, with or without the further addition 

 of other pigments. Turkey-red oil is 

 finally added to the mixture. 



Physical and Chemical Tests for 

 Acetylsalicylic Acid. 



D. E. Tsakalotos, in /. Pharm. Chun., 

 1916, 14. 174-177, states as follows: If 

 acetylsalicylic acid be heated to its melt- 

 ing point on glass, and allowed to cool. 

 it will crystallize in concentric rings. If 



heated above its melting point, it solidi- 

 fies slowly and a white porcelain-like 

 mass is formed. If the acid is fused and 

 maintained in this condition, acetic acid 

 is liberated and salicylo-salicylic acid is 

 formed. It is therefore difficult to de- 

 termine the melting point of the acid 

 with any degree of certainty. If pure 

 acetylsalicylic acid be dissolved rapidly 

 in alcohol, and water added, the resulting 

 solution does not at once show the char- 

 acteristic reaction with diluted ferric 

 chloride. If, however, the solution be al- 

 lowed to stand for some time before add- 

 ing the diluted ferric chloride, a violet 

 coloration will be noted. A sample of 

 the acid heated sufficiently to liquify it, 

 then allowed to cool and dissolved in 

 water, produces an immediate and in- 

 tense color reaction with ferric chloride. 

 If it is heated for some time above its 

 melting point, allowed to cool and then 

 dissolved in alcohol, the addition of 

 water causes a precipitation of salicylo- 

 salicylic acid, and the addition of diluted 

 ferric chloride a pale violet coloration. 

 Self's vanadium reagent for salicylic acid 

 when added to acetylsalicylic acid, in dry 

 form, does not at once show any reaction. 

 In a short while, however, a yellowish- 

 green color is produced, changing later 

 to an intense green. In case the acid 

 has been previously heated to its melting 

 point, the intense green color is noted at 

 once. If previously heated above its 

 melting point, the green color is noted, 

 but changes very rapidly to a deep brown. 

 Self's reagent may be prepared as fol- 

 lows : Dissolve a small quantity of am- 

 monium vanadate in concentrated sul- 

 phuric acid, and add water until the 

 orange color produced begins to lose its 

 intensity. The addition of formaldehyde 

 is not essential. 



