306 PROFESSOR LETTS ON PHOSPHORUS-BETAINES. 
large as pins’ heads, After some time these were collected and washed 
repeatedly with dry ether. The colourless crystals thus obtained were then 
placed in the desiccator, and after some time the iodine which they contained 
was determined volumetrically by VoLHARDT’s method. 
0°3615 required 11°5 cc. decinormal AgNO, = 0:146051 Ag = 40°5 per cent. 
1:165 ‘ 375 ,, * = 0476250 , =408 ,, 
I 
Obtained, Calculated for (CoH PC 
I, Ul. CH,—COOH. 
Todine, 40:5 408 ., : . . : 2 . AL'S 
Although these results do not exactly agree with the theoretical quantity, 
it must be remembered that the substance was not recrystallised, and was 
very deliquescent. The author considers that they prove the existence of the 
normal hydriodate, 
I 
(CoH)PC 
CH,—COOH, 
but also believes that the hemihydriodate described by Hormann exists, and 
probably also an analogous compound of the methylated phosphorus-betaine. 
Hydrate of Triethyl-Phosphorus-Betaine.—14 grms. of the carefully purified 
hydrochlorate were dissolved in water and mixed with an excess of moist oxide 
of silver. Chloride of silver was at once formed, and the solution grew warm. 
The mixture was thrown on to a cloth filter, and the solution separated from 
the chloride and oxide of silver by squeezing. A few drops of hydrochloric 
acid were then added to precipitate the silver which had passed into solution, 
and the latter was then filtered. The solution was now placed in vacuo over 
sulphuric acid, and after some days yielded a colourless syrup, which eventually 
solidified to a radiating crystalline mass. 
Some of this crystalline mass was exposed for many weeks in the desiccator 
(but not 77 vacuo), until it appeared to be perfectly dry.* 
It was then placed in a weighed tube, and exposed in vacuo at first over 
sulphuric acid, and afterwards over phosphoric anhydride. 
The vacuum was not perfect during the five or six months that the compound 
was thus exposed, but was renewed from time to time. 
At the end of this period the hydrate had ceased to lose weight. 
Altogether 0°45925 lost 0405 H,O=8'82 per cent. 
* It was reduced to powder as soon as it was partly dry, so that any water enclosed in the crystals 
might evaporate. 
eg ed 
in POs A, 2 
oF Ee Ay) eee Spry 0b Da oR ey HY BA» 
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