188 
In the apparatus brought clown for illustration and actually 
in use by the writer, there were three floating cylinders 
whose sectional areas bore the following ratios to the ring 
of water by measurement : — 
Larger cylinder 1 : 0‘925 
Medium cylinder 1: 20-610- 
Smaller cylinder .. 1 : 492"6 
In actually testing, by means of a chemical balance, the 
relation between the weights of water drawn off and the 
weights put upon a fibre, the following numbers were found : — 
Larger cylinder.. 0 926 gr. water = l grain strain. 
Medium cylinder 2L09 gr. water — 1 grain strain. 
Smaller cylinder 476*10 gr. water = 1 grain strain. 
The large discrepancy in the case of the smaller cylinder is 
owing to the difficulty of measuring it correctly ; its sectional 
area was computed to be 0-001989 inch. 
This apparatus has several advantages : the strain is put on 
in the most gradual manner, without jerks or shocks ; it can 
be put on at any rate per minute or hour, and there is hardly 
any assignable limits to either its power or delicacy, lly the 
smaller floating cylinder a strain of’ 0 - 0002 grain can be 
measured, and by increasing the size of the apparatus a strain 
of a hundred tons could be put on with the most perfect 
gradation. 
Mr. O’Neill also read a Paper, entitled “ Experiments 
and Observations upon Cotton.” 
(1.) The author began to make experiments upon the 
chemistry of cotton dyeing, but found himself compelled to 
abandon experiments upon manufactured cotton and to come 
down to the primary fibre or hairs of cotton. 
(2.) He has made very numerous experiments upon seven- 
teen samples of cotton supplied to him from reliable sources, 
and compared their physical and chemical properties. 
