PHILOSOPHICAL 
TRANSACTIONS. 
XIX. Experiments and observations on the developement of mag- 
netical properties in steel andiron by percussion. By William 
Scoresby, Jun. Esq. Communicated by Sir Humphry Davy, 
Bart. P. R. S. 
Read March 7th, 1822. 
D r. Gilbert, so early as the year 1600, discovered that 
iron became sensibly magnetic on being hammered and drawn 
out while lying in a north and south direction ; but I am 
not aware that either Dr. Gilbert, or any other person, ever 
gave to iron or steel, by this process, any considerable lifting 
power. I cannot indeed discover that any magnetical effect, by 
hammering, has been produced, beyond that of occasioning a 
deviation in the compass needle, or of giving to floating bars, 
or needles, the power of conforming their position to that of 
the magnetic meridian. 
In the course of some experiments made in the autumn of 
1820, 1 succeeded in determining, in a great measure, the 
principal laws by which the developement and destruction of 
magnetism in iron, by percussion, scowering, filing, bending, 
&c. are governed. As the result of this investigation is al- 
mdcccxxii. I i 
