a8 REPORT—187 4. 
- Bromine and iodine give similar results, Their solutions in dilute alkali. also 
evolve oxygen with the peroxide. BE syed? = ; 
In the case of iodine and peroxide the hydriodic acid formed is also acted on by 
the peroxide, so that the amount of iodine at the end of the reaction, when all the 
peroxide is decomposed, is the same as at first. A small amount of free iodine can, 
therefore, even in cold dilute solutions, decompose an unlimited quantity of peroxide. 
If an alkaline iodide or free alkali be present, then the more stable iodide is not so. 
readily decomposed by the peroxide. 
The author reserves the discussion of hypotheses until he has completed experi- 
ments with other oxygen acids of chlorine and sulphur. 
On Perchloric Acid, By T. Farnizy, 7.0.8. 
When ozone is passed into a solution of hypochlorous acid or hypochlorite, per- 
chloric acid is formed, probably thus— 
HC10+0,=HCI0,. 
Ozonized air passed through a solution of sodium hypochlorite gives a liquid 
which, in neutral solutions, precipitates potassium from its compounds as potas- 
sium perchlorate. The author is continuing his experiments to prove that the 
complete molecule of ozone is absorbed as such with a view to explaining the con- 
stitution of perchloric acid. 
The author has proved that hydrogen peroxide (2°45 per cent.) does not react on 
chloric acid or chlorates to give perchloric acid, and that no action of any kind 
takes place. The peroxide has no action on perchloric acid and its salts, which 
in this respect differ from the permanganates. The above-mentioned experiment 
is the first of its kind involving the formation of perchloric acid at ordinary tem- 
peratures, 
Electrolytic Experiments on some Metallic Chlorides. 
By Professor Guapstone and ALFRep TRIBE, 
During experiments on their air-battery the authors observed that if plates of 
copper and platinum be immersed in a solution of chloride of copper and be metal- 
lically connected, cuprous chloride is deposited on the platinum plate, while the 
copper plate is also attacked, and a galvanic current passes through the liquid from 
the metal of higher to that of lower potential. Weak external currents produce a 
similar electrolysis of Cu Cl, into Cu Cl and Cl between platinum poles, Com- 
binations of zinc or magnesium with platinum decompose cupric chloride still more 
energetically, with the production of some metallic copper as well as cuprous 
chloride on the negative plate. Precisely analogous experiments were obtained 
with mercury and gold immersed in mercuric chloride, the insoluble mereurous 
salt being deposited on the gold plate. 
— 
On the Petrified Wood of Lough Neagh. By Professor Hovers, M.D., F.C.S. 
The oceurrence along the shores of Lough Neagh, in Ireland, of masses of 
petrified wood has from very early times attracted attention, and many ancient 
writers, and several modern authorities, have ascribed to the waters of this lake 
remarkable petrifying qualities. f sit 
Bischof, in his ‘ Chemical Geology,’ also refers to the property of the water of 
petrifying wood placed in it, or rather causing its impregnation with iron, which 
induced him, he says, to make a chemical analysis of it. He, however, merely 
examined the insoluble portion of the matters left on evaporating the water, and’ 
found, contrary to what he had expected, that there was an extraordinary small: 
quantity of earthy constituents. From the suspended matter, by means of hydro- 
chloric acid, he extracted iron and alumina, but in too small a quantity to admit. 
of estimation. The fact that peroxide of iron, he remarks, is the chief constituent 
of the suspended matter, is in accordance with the statement, in the Philosophical 
