200 
Quarterly Meeting, January 24th, 1860. 
Wm. Fairbairn, Esq., F.R.S., &c., President, in the Chair. 
The following gentlemen were elected Ordinary Members 
of the Society : — Alfred Brothers, Arthur Latham, John 
Leigh, M.R.C.S., William Cawthorn Unwin, Henry Newall, 
and William Roberts, M.D. 
M. Elias Fries, Professor of Botany at the University of 
Upsala, was elected an Honorary Member of the Society. 
Henry E. Roscoe, Ph.D., F. C.S., &c.. Professor of 
Chemistry at Owens College, was elected one of the Secre- 
taries of the Society. 
¥ 
Ordinary Meeting, February 7th, 1860. 
Wm. Fairbairn, Esq., F.R.S., &c.. President, in the Chair. 
A Communication was read by the President “ On the 
Strength of Iron Ships.” 
Recent disasters have recalled to recollection numerous 
defects in the construction of iron vessels, more especially in 
their powers of resistance to a transverse strain. When we 
consider the enormous amount of life and property that is at 
stake, and dependant upon the security of these vessels, it is 
assuredly a duty to point out the defects in their construction 
and the remedies which it is necessary should be applied. 
Vessels of a length equivalent to eight or nine times their 
breadth of beam are subjected, when pitching in a heavy 
sea, to two distinct kinds of strain. First, when rising on 
the crest of a wave, the ship is supported in the middle with 
the stem and stern partially suspended ; and secondly, when 
supported at each end and suspended in the middle, as the 
waves roll under her. In these ever-changing positions it is 
obvious that her deck, as well as the lower parts of the hull, 
are subjected to alternate strains of tension and compression ; 
and the tendency is to tear the ship asunder in the middle. 
Proceedings— Lit. & Phil. Society— No. 9.— Session, 1859-60. 
