For two years I have been endeavouring to measure with 
certainty the amount of nitrogen in the organic matter, 
separating it from the inorganic. Some of the results are 
in the last “ Report of the Proceedings under the Alkali Act/’ 
and have been pretty extensively published. Other results 
are soon to be published. 
I have not yet spoken of my work, “ On the Air of 
Mines,” where drawings of the particles of solid matter are 
given (in a long report published by the Mines Commission 
in 1864), because the air was from exceptional places. 
Still similar results are got above ground. In the small 
tubes containing air from the mines and solids I was able 
to detect very distinctly organic matter and to measure 
the ammonia. 
Still the best proofs are in the sight of actual forms and 
the moving objects. In finding these with many accessories 
I consider their existence in the air of such places as were 
tried proved beyond all doubt, also long ago proved. We 
now require good microscopists to examine the individual 
forms and to find if every disease has one peculiar to itself, 
as Mr. Bailey finds every class of plants has its own peculiar 
pollen. That is probably the next most prolific field for 
those who desire something move on the subject. 
We must not be panic-stricken because of these forms. 
Some are hurtful, but it may be that others are required for 
the maintenance of healthy animal life of the highest order, 
exactly as in vegetable fermentation. We must purify the 
air within the limits of natural intention, and be careful 
that we do not overstep its boundaries. 
Professor Williamson, F.R.S., exhibited some specimens 
affording additional information in reference to the organi- 
sation of Catamites. Through the perseverance of his 
fellow-labourer Mr. Butterworth, he had now obtained, what 
he had some time ago expected to do, examples whose struc- 
