560 PROF. LETTS AND MR R. F. BLAKE ON 



Another experiment was made in a similar manner, when the same phenomena 

 recurred, the crystalline cake growing so hot that we thought it would ignite. 



The problem we had now to solve was to isolate the tertiary phosphine from the 

 numerous bye products, and this we foresaw would be no easy task, as all the operations 

 would have to be performed in closed vessels and in an inactive gas. We scarcely 

 hoped to be able to purify the phosphine by distillation, as it would almost certainly 

 have a boiling point higher than that of triphenyl phosphine, which distils above 360°. 

 The only available plan for its purification appeared to be crystallisation from alcohol. 

 Accordingly, we constructed an apparatus for liberating the phosphine, and crystallising 

 it from alcohol in hydrogen. (Fig. 2 of the Plate.) 



Experiment 1. — Twelve sealed tubes, each charged with 16 grms. phosphonium iodide, 

 12 grms. benzyl chloride, and 4 grms. zinc oxide, were heated for six hours at 120°. Their 

 contents were then transferred, as we have described on p. 541, to a flask, and the primary 

 phosphine liberated by water and steam and distilled off. The residual brown resinous 

 mass was steamed three times with water, and was then transferred to the flask A, and 

 drained from water as far as possible. 50 grms. of potash were dissolved in 400-500 c.c. 

 of alcohol ; the flask A connected with the condenser, filled with hydrogen, and the 

 potash solution added through C. D was then closed (with an india-rubber tube and 

 a glass rod), and C left open for the escape of hydrogen. The mixture in A was then 

 boiled for about three hours, during which a gentle stream of hydrogen was allowed to 

 flow through the apparatus. C was now closed. D connected with E, and pushed down 

 so that its end was at the bottom of A. The hydrogen thus forced the liquid into F 

 (previously filled with the gas), when it was filtered into H. As it cooled crystals 

 separated, but in addition an oily liquid also. After the lapse of some time H was closed 

 by the pinchcock G, F disconnected, the ends of K and I closed, and H inverted. The 

 alcoholic mother-liquors were separated from the crystals and oily liquid by attaching K to 

 the hydrogen generator, and opening G, when they were forced out. The crystals and oily 

 liquid were washed twice with water added through G. Next, after draining off the 

 water, alcohol was run in and the crystals boiled with it, while a stream of hydrogen passed. 

 On cooling both the crystals and oily liquid separated out again. The mother-liquors 

 were drained off as before, and the crystals and oil dried in a stream of hydrogen (H 

 being placed in boiling water)., 



An attempt was then made to separate the phosphine by distillation in vacuo, but 

 without success. A little liquid passed over at first, but free phosphorus soon separated, 

 and the temperature suddenly rose above 360°, with complete decomposition. 



There had remained in the funnel F, in this experiment, a considerable quantity of 

 a dirty oily liquid mixed with some crystals. It was washed two or three times with 

 water, and was then examined. 



(1) A portion mixed with iodide of methyl soon reacted, the mixture grew very hot 

 and entered into ebullition, and after a short time an oily liquid resulted. 



(2) Another quantity was mixed with crystallised iodide of benzyl, when a good deal 



