440 
PHARMACEUTICAL MEETING. 
there stated that when peroxide of barium was treated with an acid solution 
of bichromate of potash, oxygen was evolved. The same fact had also been 
adverted to by Professor Faraday, in a lecture at the Doyal Institution. If 
Professor Brodie had patented the process spoken of at the time at which he 
referred to it, the patent would have been on the eve of expiration. When 
he (Dr. Squire) saw the subject of Mr. Dobbins’s paper announced, he imme¬ 
diately remarked that the process would no doubt consist in the use of pre¬ 
cisely the compound which had been introduced to the meeting. He did not 
consider that the matter was sufficiently new to become the subject of a pa¬ 
tent, but it would probably add to the number of instances tending to show 
the nuisance occasioned by chemical patents. 
Mr. Dobbins was not aware of the notice referred to in Professor Brodie’s 
paper, although he was aware that the general nature of the reactions of per¬ 
oxide of hydrogen was known to chemists. What he claimed in his patent was, 
the practical application of a known principle to a useful purpose, in the pro¬ 
duction of oxygen gas by a very easy method. 
Mr. C. H. Wood said it was true that the reaction of peroxide of barium 
and bichromate of potash in the presence of an acid was known before the 
date of Mr. Dobbins’s patent, but it was by no means certain that this would 
invalidate the patent. He thought the principal objection to the process was 
the cost of the oxygen obtained by it, which was several times greater than it 
was when made from chlorate of potash. He could not even accede to the 
new process any advantage over the old process, with regard to the facility 
with which it was performed. But then Mr. Dobbins claimed for his process 
the production of oxygen gas in a greater state of purity than it was obtained 
in by the action of heat on chlorate of potash and oxide of maganese, and he 
represented the gas produced by the latter process as contaminated with 
chlorine, and attempted to prove this by showing that it decomposed iodide of 
potassium, setting iodine free. This test, however, was insufficient to prove 
the presence of chlorine, as it gave a similar reaction with ozone or active 
oxygen. The late Mr. Witt had shown that oxygen obtained from chlorate 
of potash always contained a certain amount of ozone, and he (Mr. Wood) 
thought it was worth considering whether the medicinal efficacy of oxygen, if 
any, was not likely to be due to it in the active rather than the inactive state. 
Dr. DEDw r ooD thought it was due to Mr. Dobbins to state, with reference 
to the presence of chlorine in oxygen made from chlorate of potash, that the 
subject was some years ago investigated by Mr. Crace Calvert, who came to 
the conclusion that chlorine or an oxide of chlorine was contained in the gas. 
He (Dr. Dedwood) was inclined to confirm this view from his own experience, 
and he thought if the effect of inhaling oxygen was being tried, it was desir¬ 
able that pure oxygen should be used for the purpose. Mr. Dobbins was en¬ 
titled to the merit of having introduced a process by which oxygen gas was 
produced in a state of great purity, in which it was w T ell suited for inha¬ 
lation ; and this process appeared also to present some advantages in the faci¬ 
lity with which it was performed. It was certainly not so economical as the 
process usually adopted, nor was it likely to supersede that process in the 
laboratory while the price of the materials continued as at present; but if 
oxygen should be required to be made by medical men or by non-professional 
operators, Mr. Dobbins’s process would be found a convenient one. Although 
the principle involved was not new, the application, he believed, was so, and 
he would be sorry to say or do anything to deprive the author of the credit to 
which he was entitled, or of any more substantial advantage he might hope to 
derive from it. 
The 'President fully appreciated the practical importance of the process 
introduced to their notice by Mr. Dobbins. He had occasion recently to pro- 
