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shade. The only question now was as to its containing indigo 
in quantity sufficient to render the importation profitable. 
The solution of this question being partly one of chemical 
manufacture, has been undertaken by Mr. R. llumney, who 
is to operate on a large quantity so as to get results of 
commercial value. 
Mr. Spence was chiefly induced to bring this subject before 
the Society from the fact that a new source of indigo at the 
present time would be a matter of great importance to trade, 
the growth of the article in India being from peculiar causes 
rather on the decline. 
Dr. Schunck corroborated Mr. Spence’s statements so far 
as that he had found indigo fully formed existing in the 
specimens submitted to him ; he had not had time as yet to 
ascertain what quantity of that body they contained. 
Mr. Mosley stated that it had been known for some time 
that the indigo plant grows wild in many parts of the West 
Coast of Africa ; he believed it would be of great importance 
at present if a new source of indigo could be found, as the 
Indian manufacture seemed to be declining. He believed the 
manufacture had been attempted in Africa, but had not 
succeeded. 
The Rev. Robert Harley, F.R.A.S., communicated to 
the Society the following statement on the Theory of the 
Transcendental Solution of Algebraic Equations : — 
Certain published Papers of Mr. Cockle, as well as some 
private communications from that mathematician to myself, 
have led me of late to study the theory of equations under a 
new and interesting aspect. 
Let f ( y , x) = 0 be an algebraic equation of the «th degree 
in y , and such that its roots y h y 2 , . . .y„ are all functions ^of 
a single parameter x. From this equation we may deduce a 
linear differential equation of the (n — l)th order which it 
is proposed to call “the differential resolvent.” The n roots 
