i88o.] and Peroxide of Hydrogen. 365 
affirmation made at the beginning, that there is not , and never 
was , antozone . 
II. Peroxide of Hydrogen. 
Though peroxide of hydrogen was discovered by Thenard 
more than half a century ago (1818), and has ever been a 
substance possessed of unusual interest in the eyes of che- 
mists, yet the difficulties of its manufacture were so great 
that only recently has it ceased to be a chemical curiosity 
and come into use in the arts. Only a year ago a very dilute 
solution of the peroxide, imported from Europe, was sold 
in New York at the price of 16 dollars per gallon. But 
to-day a solution containing 8 to 10 per cent is retailed at 
about 1 dollar per lb. At this high price it is sold under 
fanciful names, and employed to bleach the hair, being used 
— as Dr. Warren would have styled it — as an Anticyano- 
chaitanthropopoion or Tetaragmenon Abracadabra, to change 
the dingy tresses of the titmice among the ladies to a ra- 
vishing tow. But there is much reason for believing that a 
most important future is before it ; and whether in the 
chemist’s laboratory or in the arts, as a most powerful 
oxidising and reducing agent, — for it can aft as both, — for 
bleaching purposes, &c., it is destined to play a great part. 
With its cheapening, many new uses will be found for it, 
and it is probable that before very long it will take its place, 
as Mr. G. E. Davis has strongly urged (“ Chemical News,” 
xxxix., p. 220), as an indispensable article upon the working 
table of every chemist. 
But it is not these considerations which mainly interest 
us in connection with its scientific history. It is rather 
the accessions to our knowledge, which, more especially of 
late, have elucidated many obscure points connected with 
its sources and properties. That the method of preparation 
from peroxide of barium and hydrochloric acid (Thenard, 
1818), or from the same oxide and carbonic acid (Duprey, 
1862 ; Balard, 1862), is not used to obtain it on a commer- 
cial scale, is familar to many, the method of Pelouze, in 
which hydrofluoric or fluosilicic acid is employed to effect 
the decomposition, being that employed in the arts. 
That peroxide of hydrogen was formed in the electrolysis 
of water strongly acidulated with sulphuric acid was stated 
by Meidinger (1853), and was apparently so well confirmed 
by the experiments of Bunsen (1854), C. Hoffmann (1867), 
and others, that until the researches of Berthelot (1875) 
were published the production of peroxide of hydrogen in 
electrolysis was looked upon as a fully established fact. 
