16-4 PROCEEDINGS OF THE AMERICAN ACADEMY. 



Preparation of Formylchloridoxime from Silver Fulminate. — Fulmi- 

 nate of silver is best obtained as follows. 5 grams of silver are dis- 

 solved in 100 grams nitric acid (sp. gr. 1.34), and the warm solution 

 is poured into 150 c.cm. alcohol (90 per cent) and then heated for 

 5 to 10 miuutes on a water bath until a reaction sets in. The reac- 

 tion then continues very energetically, of its own accord, and silver 

 fulminate separates out in beautiful needles. The yield is regularly 

 6.5 grams or more, and the filtrate contains only traces of silver. The 

 salt is much less soluble in boiling water than Liebig states.* In the 

 dry state it is far more dangerous than the mercury salt : it explodes 

 instantly, and with tremendous violence, on touching it very care- 

 fully with a platinum spatula. It can, however, be dried without the 

 slightest danger on filter paper, and collected therefrom by means of a 

 camel's hair brush. A silver determination of the salt, dried over 

 sulphuric acid in a vacuum, gave the following result. 



0.2013 gram substance, digested with dilute hydrochloric and nitric 

 acids, gave 0.1925 gram AgCl. 



Theory for AgONC. Found. 



Ag 72.00 71.92 



In order to convert silver fulminate into formylchloridoxime, 12 

 grams salt are added to 80 c.cm. hydrochloric acid (one part concen- 

 trated acid to one part water) containing pieces of ice, and then, after 

 decanting or filtering from the chloride of silver, proceeding as above 

 in the case of the sodium salt. A small portion of the concentrated 

 ethereal solution of formylchloridoxime was evaporated as above, and 

 the substance immediately analyzed : the chief portion was treated 

 directly with 12.5 grams of aniline (2 molecules) and thus converted 

 smoothly into phenylisuretine (see below). 



0.4478 gram substance gave 0.7758 gram AgCl. 



Theory for CH,N0C1. Found. 



CI 44.65' 42.68 



Properties of Formylchloriiloxime. — The formylchloridoxime ob- 

 tained in these two ways is a very reactive and remarkable substance. 

 In the solid condition, or in concentrated ethereal solution, it can be 

 kept at 0° for some time unchanged. It volatilizes very quickly and 

 completely, in small portions, at ordinary temperature, and this serves 

 as a good means of determining its purity. It often happens, when all 

 possible precautions in its manufacture are not observed, that a pro- 



* Annales flc Chim. et de Phys., XXIV 297 



