PROFESSOR LETTS ON PHOSPHORUS-BETAINES. 29% 
“The base forms with hydriodic and nitric acids well crystallised salts. The 
iodide is easily obtained by dissolving the free base in hydriodic acid, evaporat- 
ing the solution to dryness, washing the dry substance with a little absolute 
alcohol to remove free iodine, and then crystallising the decolorised salt from 
hot alcohol. 
“The iodide is easily soluble in water, and crystallises in beautiful leaflets. 
An estimation of iodine shows that the composition of the salt is, 
C,H.(CH,),PO,.HI. 
“Thus the normal iodide had been obtained, a fact which is somewhat 
remarkable, as, according to HorMann’s researches on the corresponding ethyl 
compound, both of the phosphorus and nitrogen series, a molecule of the base 
is found associated with the iodide. 
“The nitrate is very soluble in water; the solution crystallised, but less 
easily than that of the iodide. I have not analysed the salt. 
“ This also was the case with the free base, which is so hygroscopic that the 
analysis could only have been performed with difficulty. 
“ But in the face of so many analogies, it cannot be doubted that in this case 
also, by the action of oxide of silver on the chloride, an exchange of chlorine 
for hydroxyl does not occur, but in its stead a separation of hydrochloric acid, 
in consequence of which the compound would be, 
(CH;),C,H,O.P a C,H,(CH3),PO, ’ 
i.é., trimethylated phosphorised glycocoll, or the betaine of the phosphorus 
series,” 
The Materials necessary for the Research.* 
The materials necessary for the research which the author determined to 
undertake were chloracetic and bromacetic acids, and trimethyl-phosphine 
or triethyl-phosphine. The former were purchased from Messrs KaHLBAuM 
& Co. of Berlin, whose preparations the author has always found may be 
relied on. But the trimethyl- and triethyl-phosphine are substances not 
readily purchased, and it was considered better for many reasons to prepare 
them. 
No difficulties were expected in accomplishing this, as Hormann has 
recently published a method which is stated by him to give excellent results, 
* Owing to the expensive nature of the materials necessary for these experiments the author 
applied in 1879 (when they were commenced) for a sum of money from the Government Research 
Fund, which was granted him. He takes this opportunity to acknowledge the assistance thus received, 
without which he would probably have abandoued the research long before its conclusion. 
