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



production of the phosphoric acid (15*4 grms.). And that this supposition is a true one 

 is also clearly shown by the rise in temperature which takes place when the product of 

 the reaction is treated by water, and by the complete change which occurs in its 

 appearance, as well as by the fact that the weight of products is greater than the collec- 

 tive weights of phosphorus, benzyl, alcohol, and iodine originally taken. 



It is also quite possible that the whole of the tribenzyl phosphine oxide is formed by 

 the action of caustic baryta on iodide of tetrabenzyl phosphonium produced in the first 

 instance : but we have not decided this point. 



(4) The quantity of benzyl alcohol employed is less than the quantity calculated as 

 being equivalent to the weights of the different substances obtained. The difference, 

 however, is not great (about 5 per cent.), and is accounted for, no doubt, as we have 

 explained. 



The reaction with benzyl alcohol is a very interesting one, and we believe that it is 

 capable of extension to other alcohols. Some preliminary experiments which we have 

 made justify us in this belief, and we intend to pursue the inquiry. 



