30 R. THRELFALL. 
would not account for the ‘result. Consequently, the chemical 
theory of the frictional machine may be said to be placed on 4 
sound basis. At the same time it is only fair to say that Mn — 
Lea’s experiments have not yet been confirmed. A year ago rT ; 
began to conduct a check series of experiments by another method, 
but I have not had time to carry them through. | 
T ought perhaps to have curtailed my remarks on my own — 
work rather more, but I wished to show that problems of the — 
very first importance are to be approached in the domain of 
physical chemistry, and I naturally took that part of the subject : 
with which I am best acquainted, to form a basis for my 
remarks, 
A Conrrisution to tore CHEMISTRY or AUSTRALIAN 
MYRTACEOUS KINOS. 
By J. H. Marpen, F.1.s., &c., and Henry G. Situ. 
[Read before the Royal Society of N. 8. Wales, June 5, 1895.] 
In the investigations that have been carried out at the Techno- | 
logical Museum during the last few years, on the exudations of 
the Australian Myrtacex, it has been found that these substances / 
known as kinos fall into three classes, which have been respec” 
tively named the Ruby, Gummy, and Turbid groups. The — 
members of the first of these are soluble both in alcohol and water; — 
giving a ruby coloured solution, those of the second are practically ; 
insoluble in alcohol, and the third, when treated with hot water — 
and allowed to cool, contain a body or bodies which render the 
liquid turbid. | 
We now deal with kinos belonging to this last group, the present 
investigation having been carried out with the view to identify 
the substances causing the turbidity already referred to. 
