152 EXPERIMENTAL FARMS 



2-3 EDWARD Vll^ A. 1903 



(5.) Sample from centre of bottle. This sample contained 75-04 p. c. sodium 

 cyanide, equivalent to 41-41 p. c hydrocyanic acid. 



No. 2. — Bottle labelled ' Potassii Cyanidum, Double Salt' The Elliott Company, 

 Ltd., Toronto. The bottle contained 4 oz. ; the cork was covered with a paper seal but 



not waxed. 



Examination showed this to be potassium cyanide with traces or small amounts 

 only of the corresponding sodium salt. A determination of the potash gave data equi- 

 valent to 98*7 p. c. potassium cyanide. 



(a.) Sample from top of bottle. This gave the following results : — Potassium cya- 

 nide 77-24 p. 0., equivalent to 32-05 p. c. hydrocyanic acid. 



(6.) Sample from centre of bottle. This showed 95-66 p. c potassium cyanide, 

 equivalent to 39 • 62 p. c hydrocyanic acid. 



Na 3. — Sample labelled ' Pot. cyanide 98 p. c, Lyman, Sons & Co., Montreal. 

 Contained in 2 oz. bottle. 



Qualitative examination showed this to be potassium cyanide. 



Analysis : Potassium cyanide, 94 • 9 p. c, equivalent to 39-3 p. c. hydrocyanic acid. 



No. 4. — Sample labelled 'Pot. cyanide 98 p. c, Lyman, Sons & Co., Montreal. 

 Contained in 2 lb. glass stoppered bottle. Sample for analysis taken from centre of bottle. 



Qualitative examination : potassium cyanide. 



Analysis : Potassium cyanide, 94 • 69 p. c, equivalent to 39 • 26 p. c. hydrocyanic acid. 



Conclusions and Stiggesiions. 



Chemically pure, water-free sodium cyanide would yield 55-18 p. c. hydrocyanic 

 acid. Chemically pure, water-free potassium cyanide would yield 41-49 p. c. hydro- 

 cyanic acid. 



Tabulating the results, we have : — 



Hydrocyanic acid. 

 Per cent. 



Sodhim cyanide, pure and water-free 55 • 18 



Potassium cyanide " 41-49 



Sample No. 1, sodium cyanide, from top of bottle 33-26 



" " centre of bottle 41-41 



Sample No. 2, potassium cyanide, from top of bottle 32-05 



centre of bottle 39-62 



Sample No. 3, potassium cyanide, average of bottle 39-30 



Sample No. 4, potassium cyanide, centre of bottle 39-26 



It is a matter of little moment perhaps that the cheaper base soda should be sub- 

 stituted for potash (indeed, weight for weight, pure sodium cyanide will evolve moi-e 

 hydrocyanic acid gas than pure potassium cyanide), but it is of the greatest importance 

 that the cyanide should be of the strength specified and yield the amount of hydrocyanic 

 acid gas as calculated from that strength. The cyanides are extremely subject to deterior- 

 ation. The action of the air, as entering through a poor cork, is sufficient to cause 

 decomposition, resulting in loss of gas generating strength, as may be observed from the 



foregoing results. 



All the samples examined were below advertised strength, but this, we believe, Avas 

 not owing to intentional act or fraud on the part of the vendors, but merely to imper- 

 fect protection from the air. Most probably the cyanide v/ill be found to retain its 

 strength better when kept in large bottles. When, however, it is desired to have it in 

 small doses, as one, two and four ounces, decomposition of the cyanide may be very 

 largely retarded by thoroughly coating the surface of the cork with paraffin wax. 



CALIFORNIA SPRAY. 



(Lime, Suljihur atid Salt.) 



Tliis mixture has recently received considerable attention in the horticultural press 

 in connection with the remedies for the San Jose scale, and several formulae with vary- 



