PROFESSOR LETTS ON PHOSPHORUS-BETAINES. 317 
carbonate of silver when it was mixed with nitrate of silver. It also had a 
very faint acid reaction. 
Now all these properties are those of a bicarbonate, and there can be little 
doubt that the hydrate is converted by heat into the isomeric bicarbonate of 
triethyl-methyl-phosphonium. 
Thus--- 
That the phosphonium salt had been formed was proved not only by the 
characteristic form of its chloroplatinate, but also by an analysis of the latter. 
0:5484 orm. gave 01610 Pt = 29-4 per cent. 
05484 gave 0698 AgCl=01726 Cl= 315 _,, 
Obtained. Calculated for 2 {(C,H,),(CH,)PCI}, PtCl,. 
Platinum, : 29°4 : : ; we 
Chlorine, ‘ 31°5 : : : - ol 
Action of Heat on the Sulphate.—The sulphate when heated behaves like the 
other compounds which have been spoken of. It fuses, effervesces from escape 
‘of carbonic anhydride, and then solidifies. The solid residue was converted 
into chloroplatinate, which crystallised in the characteristic form of the triethyl- 
methyl-phosphonium compound. It was not considered necessary to analyse it. 
The decomposition of the sulphate, there can be no doubt, is expressed by 
the equation, 
CH,—:C00:H CH, 
(CHJ=PC — (C,H,),=P 
SO, = SO), 200.) 
O,H =PC es | O,H,),=P 
( 2 5) OH, — 000'H ( Phase ie) OH, 
The preceding experiments show that the compounds of triethyl-phosphorus 
betaine behave in exactly the same manner when heated, as the oay-salts of 
dimethyl-thetine, and in this respect are utterly unlike the compounds of the 
true betaine. 
Here then we have another of the many examples in which analogous 
compounds of phosphorus and sulphur display similar properties, whilst the 
corresponding nitrogen compounds behave differently. It should be remarked, 
that the author has in vain sought for a compound of phosphorus analogous 
to thio-diglycollic acid, viz., P(>CH,COOH),. Neither by the action of heat 
on any compound of the phosphorised betaine, nor by other reactions which 
might be expected to give rise to this body, could it be obtained. The author, 
VOL. XXX. PART I. 3 C 
