101 
Ordinary Meeting, February 22nd, 1870. 
J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the 
Chair. 
The President referred to the observations he had made 
in former years on the progressive rise of the freezing point 
of one of his thermometers, published in the Proceedings 
for April 16, 1867. He had made a further observation on 
the 12th February instant, and found that a rise, which 
though very small was unmistakable, was still taking place 
after a lapse of time of 26 years since the bulb was blown. 
The results are as follow in indications of the thermometer, 
calling the first observation in April, 1844, zero. 12 ‘9 
divisions of the thermometer correspond to one degree 
Fahrenheit. 
April, 1844 0 
Feb., 1846 5-5 
Jan., 1848 6*6 
Feb., 1853 8-8 
April, 1856 9-5 
Dec., 1860 Ill 
March, 1867 IDS 
Jan., 1868 11 -92 
Feb., 1870 12*02 
Dr. F. Grace Calvert, F.R.S., stated that he did not 
intend to read a paper on artificial alizarine , some 
of the facts he was going to bring before the notice of the 
o o o 
meeting, being well known to his colleagues the chemists of 
this district, but he hoped it might be interesting to the gene- 
ral members of the Society to have an idea of the progress 
that had been made during the last few months in the produc- 
tion of this substance. They were aware that alizarine 
was the essential colour- giving principle of the madder root. 
Peooeedin&s — Lit. & Phil. Society. — Vol. IX. — No. 11. — Session 1869-70. 
