460 MR. G. B. BUCKTON AND DR. A. W. HOFMANN’S RESEARCHES ON THE 
2 equivs. of Carbon . 
( 
. . 12 
Theory. 
— ^ ^ 
571 
Mean of experiments. 
5-32 
10 equivs. of Hydrogen . 
. . 10 
476 
5-22 
4 equivs. of Sulphur. . 
. . 64 
30-47 
30-55 
2 equivs. of Nitrogen . 
. . 28 
13-33 
12-98=*^ 
12 equivs. of Oxygen 
. . 96 
45'73 
45-93 
210 
100-00 
100-00 
Disulphometholate of Potassium 
is most readily obtained by adding- the crystallized barium-salt by degrees to a boil- 
ing solution of carbonate of potassium^ avoiding an excess of the former. After 
filtration, the new substance separates easily from excess of alkali in fine shining 
needles or brilliant grains, according to the rapid or slow precipitation from its solu- 
tion. It is not very soluble in cold water, one part requiring fourteen parts of water 
at 22° C. for solution. 
Disulphometholate of Zinc. 
When metallic zinc is heated with an aqueous solution of the acid, hydrogen gas is 
liberated, and on concentration a syrup is formed which crystallizes with great dif- 
ficulty. Alcohol does not precipitate this salt from its solution. 
Disulphometholate of Lead 
forms small square nacreous plates not unlike those of the barium-compound. It 
is very soluble in water. 
Disulphometholate of Copper 
is produced by careful precipitation of the barium-salt by sulphate of copper. It 
yields radiated needles or small prisms of a green colour. They are insoluble in 
absolute alcohol, but soluble in spirits of wine. 
We have not succeeded in preparing the ethers of this acid. We anticipated that 
they would be formed by bringing together iodide of ethyl and disulphometholate of 
silver. A strong solution of the silver-salt reacts at once on the iodide without 
application of heat. Iodide of silver is precipitated, but the ether which is formed 
splits immediately into disulphometholic acid and alcohol, according to the equation 
Ca (Ha Aga )S4 Oiad-2C4 H5 I-j-4HO = 2Ag I-1-2C4 Hg Oa+Ca H4 S4 Oia. 
* The mean of nitrogen in Experiments III. and IV., viz. 13‘11 and 12-85. They were made with speci- 
mens of different preparations. 
