TY  - JOUR
T1  - Geometrical Investigations concerning the Phaenomena of Terrestrial Magnetism: Second Series,--On the Number of Points at Which a Magnetic Needle Can Take a Position Vertical to the Earth's Surface. 
JF  - Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London (1800-1843)
VL  - 3
SP  - 368
EP  - 371
PY  - 1830/01/01/
UR  - http://dx.doi.org/10.1098/rspl.1830.0228
M3  - doi:10.1098/rspl.1830.0228
AU  - Davies, T.
ER  -