191 
" That the thanks of the Society be given to the Philosophical 
and Literary Society of Leeds, for their kindness in affording the 
use of their Museum and Hall to the Society. 
" That the thanks of the Society be given to Edward Sheardown, 
Esq., of Doncaster, for a donation of Fossils from the Northum- 
berland and Durham coal field. 
" That the thanks of the Society be given to the Royal Cornwall 
Polytechnic Society for a copy of their transactions." 
Mr. Wilson exhibited a specimen of Dr. Albert's steam 
fuel. 
Mr. Embleton read a paper, written by Mr. Chas. Todd, 
of the firm of Shepherd & Todd, makers of locomotive 
engines, Leeds: — 
EXPERIMENTS ON THE RELATIVE STRENGTH OF PIG IRON 
OF VARIOUS QUALITIES, AND FROM DIFFERENT MAKERS, 
UPON BARS 12 INCHES LONG, BY 1 INCH SQUARE. 
BY MR. CHARLES TODD, RAILWAY FOUNDRY, LEEDS. 
The following experiments were made with a view to 
ascertain the merits, in point of strength, of some of the 
difi'erent British pig irons which are brought into our market. 
Almost every manufacturer, or his agent, tells us that his 
own pig iron is the best and strongest which is made ; and 
therefore, excepting an iron founder be mindful to test 
the iron which he buys, he is not only liable to be imposed 
upon, but to produce from his foundry such an article as 
may, from time to time, incur to himself serious pecuniary 
losses, and injure his reputation as a respectable tradesman 
and iron founder. They were also undertaken with a view 
to ascertain what mixtures of the difierent pig irons would 
give the strongest and soundest grain. 
All the experiments here noted were made upon bars cast 
from the same model ; taken from the sand without any 
dressing, such as chipping or filing; tested with the same 
