l54 ®N SUPERACID AND SUBACID SAtTS. 



Butiti&ac. invented by Dr. Traill, as well as of those previously in- 

 once' and wUh ^'^"^^^^^ unknown to him, and here mentioned by Mr. Bancks, 

 facility. appears to me to consist in the being able by its means to 



exhaust the receiver in a very considerable degree, at a sin- 

 gle operation, and without any labour. This great saving 

 of time may be an object of importance on some occasions; 

 as I conceive the exhaustion would be considerable, though 

 not complete, or even equal to that of an air pump of the 

 best kind: for nothing in the remarks of Mr. Bancks con- 

 tradicts this, and the opinion of Dr. Traill is not merely 

 theoretical, since he rests it on his own experience, though 

 he had not the advantage of an able artist. 



II. 



On Superacid and Subacid Salts. By William Hyde 

 Wo LL ASTON, il/. D. Sec. R. S*. 



Superoxalafes ^'^ *^^ paper which has just been read to the Societyf, 

 have a double Dr. Thomson has remarked, that oxalic acid unites to stron- 

 p r ion aci , ^|^^ ^^ y;G\\ as to potash in two different proportions, and 

 that the quantity of acid combined with each of these bases 

 in their superoxalates is just double of that which is satu- 

 rated by the same quantity of base in their neutral com- 

 poundsf. 

 The same law As I had observed the same law to prevail in various 

 other instances of superacid and subacid salts, I thought it 

 not unlikely, that this law might obtain generally in such 

 compounds, and it was my design to have pursued the sub- 

 ject with the hope of discovering the cause, to which so re- 

 gular a relation might be ascribed. 

 Thisonecase •'^"'- since the publication of Mr. Dalton's theory of che- 

 of a more ge- mical combination, us explained and illustrated by Dr. 

 se%^ed by Mr ThomsoniJ:, the inquiry which I had designed appears to be 



holds in other 

 irwtances. 



Daltou. 



* Philos. Trans, for 1807, p. 95. 



"l" See our Journal, p. 19 and 22 of the present -vol. 



X Thomson's Chemistry, 3d Edition, Vol. Ill, p. 425. 



superfluous* 



