15G 
Ordinary Meeting, November 1st, 1859. 
J. P. Joule, LL.D., F.R.S., Vice-President, in the Chair. 
Attention was drawn to the extreme depression of the 
barometer which had occurred during the day. About noon, 
in Manchester, the mercury stood at 28-4 inches. At Bel- 
field, near Rochdale, Dr. Schunck observed an atmospheric 
pressure of only 28*12 at nine o’clock, a.m. 
The Chairman stated that he had received a letter from 
Professor Thomson, explaining that, although he had men- 
tioned five per cent of loss per minute as a perfection of 
insulation easily attained in his apparatus, he found that by 
carefully selecting the glass stems, and having the atmosphere 
in which they are placed well dried by sulphuric acid, the 
loss by imperfect insulation of the testing conductor might 
readily be diminished to five per cent, per hour. He had 
found also that the Leyden phial, to the inside coating of 
which the index was connected, did not lose as much as one 
per cent, per day even when the instrument was exposed to 
sea spray in a boat, to rain, and to fog, besides experiencing 
great changes of temperature. 
N.B. The observations recorded in the last number of the 
Proceedings, as having been made on the 3rd and 4th of 
October, were made on the 10th and 11th of that month. 
A Paper was read by Mr. James G. Lynde, M. Inst. 
C.E., F.G.S., entitled, “ Experiments on the Strength of 
Cast Iron Girders.” 
The Paper was accompanied by a diagram, shewing the 
riiocEEDiN'QS— Lit, & Phil. Society— No. 3.— Session, 1859-CO. 
