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similar process is applicable to the more general resolvent. 
But what is wanted is a solution without the aid of definite 
integration. 
Sir John F. W. Herschel, in a letter to me under date 
March 15th, 1862, referring to the closing remark in my last 
communication, calls attention to a paper of his in the 
“ Philosophical Transactions” for 1814, “ On various Points 
of Analysis,” “§ IV. On Equations of the First Degree,” and 
also to a paper of his in the “Memoirs of the Analytical 
Society” of Cambridge, 1813, “On Equations of Deferences,” 
in which there is something. Sir John Herschel thinks, tend- 
ing to confirm the opinion that the primary forms of inte- 
grable linear differential equations stand in close connexion 
with the solvable forms of algebraic equations. In the latter 
paper, however, Sir John Herschel informs me that he wishes 
to “repudiate all that occurs from page 100 to page 105, as 
founded on a mistake.” I need hardly add that the writings 
of so distinguished a member of our Society shall receive, as 
they deserve, my most careful attention. I hope soon to 
return to the subject. 
Dr. R. Angus Smith, F.R.S., read a Paper entitled 
“ On the Putrefaction of Blood, No. 2.” The following 
is an abstract. 
"When I first began to examine the products of the putre- 
faction of blood, it was merely with the object of ascer- 
taining the nature of the gases, and of ascertaining whether 
any matter in them exists in a so-called organic condition, 
and, if so, in what quantity. I have ascertained the nature 
of the gases. So far as I see, however, I have added no new 
one, but I believe that for the first time I have given the 
proportionate amount of each. 
I have also decided on a simple and certain method of 
collecting some organic substances from the gases, namely, 
the use of caustic potash, "which I find superior to acid salts. 
