131 
Ordinary Meeting, March £lst, 1865. 
E. Angus Smith, Ph.D., F.R.S., President, 
in the Chair. 
Dr. Joule described an instrument he had constructed for 
showing rapidly minute changes of magnetic declination. 
The adjoining sketch represents a sec- 
tion half the real size, a is a column 
of small magnetic needles suspended by 
a filament of silk. Attached to its 
Proceedings Lit. & Phil. Society — Vol. IV.— No. 13 .— Session 1861-5. 
