xc GENERAL SUMMARY OF SCIENTIFIC AND 



mend more especially, however, the amylsulphocarbonate of 

 potassium as being cheaper, costing only about fifteen cents 

 per pound. 



Kolbe has further investigated the fact, observed by his 

 assistant, Ost, that while sodium silicate yields on dry distil- 

 lation sodium sodiosalicylate, potassium salicylate similarly 

 treated yields potassium paraoxybenzoate. He finds that 

 the barium, strontium, calcium, and magnesium salts act like 

 the sodium salt, and that the potassium salt does the same 

 when heated only to 145. He recommends this as the best 

 method for the preparation of paraoxybenzoic acid. A series 

 of papers lias been published in Kolbe's Journal by Neu- 

 bauer, Kolbe, Wagner, Fontheim, Ziirn, and others upon the 

 antiseptic action of salicylic acid. It has come very ex- 

 tensively into use, having, for example, entirely replaced 

 phenol in the lying-in hospital of Leipsic. 



Weiske proposes the use of salicylic acid in titrition, es- 

 pecially in acid ime try. A convenient quantity of it is dis- 

 solved in distilled water, and a few drops of ferric chloride 

 solution is added. To the intensely colored solution soda 

 solution is added to exact neutralization, the color changing 

 to yellowish-red. If a few cubic centimeters of this liquid be 

 added to the acid to be titered, the color becomes of a deeper 

 violet as the soda solution is added, reaching its highest in- 

 tensity just before neutralization, and becoming colorless on 

 the slightest excess of alkali. 



Knop has made a series of experiments to ascertain the 

 action of salicylic acid upon vegetation. He finds that it has 

 a marked depression of action upon the vegetative activity 

 of cells, whether these be the chlorophyl cells of the higher 

 or the non-chlorophyl cells of the lower orders of plants, pro- 

 vided only the acid be free. Of fifteen grains of corn soaked 

 in water containing - 2 - * u of this acid, fourteen failed to 

 germinate. Moreover, mould is prevented by a quantity of 

 salicylic acid as minute as this. 



Rautert has given an improved method of purifying sali- 

 cylic acid by distilling it in a current of superheated steam. 

 Recrystallization from water makes it snow-white. 



Kolbe lias thoroughly investigated the properties of his 

 "salylic acid" obtained by reducing chlorsalylic acid with 

 sodium amalgam, and has come to the conclusion that it is 



