( 3‘i ) 
ixiuft more powerfully increafe the Attradion of the 
North Pole ; x\nd (ince the Poles mutually aflift one 
another’s Attraclion, with a Power much greater than 
if they themfelvcs are not aflifted, the conjund Poles 
muft neceffarily lift at lead twice fo much as both of 
them can lift feparately. I once tried, and found the 
South Pole armed to lift 1115’ Grains, and both Poles 
united 5760 with a little more Difficulty. The Ratio is 
about I to a little more than 5’. 
XXI. That if a Bar of Iron or Steel (not having the 
lead Degree of fixed Vertue) is placed in any Podure 
(except at, or near to a right x\ngle with the magnetical 
Line) it will not only for the prefent receive a tranfi- 
ent Polarity thereby, but if it fo remains long enough, 
the faid Polarity will gradually become fixed or per- 
manent, more or lefs, according to the Hardnefs or 
Softnefs of the Bar, Time it has remained in that Po- 
fition, Angle its Length makes with the magnetical 
Line, and Proportion of the Length thereof to its Big- 
nefs, the longed {cateris part ihiis'^ ufually receiving 
mod Vertue : And fomerimes when all thefe Advan- 
tages concur, the Polarity will be fenfibly permanent 
in a little Time, and not require a very long Time to be 
rendered pretty drong. 
XXII. That by placing the faid Bar afterwards in 
the fame Pofition, only with its Ends (hided, it will 
gradually lofe its gained Magnetifm, and at length have 
its Polarity changed* 
XXIII. Mr. Boyle found one of his Loaddones 
much impaired by lying long in a. wrong Podure, I 
fuppofehe meant a repelling one, with its North Pole 
towards the North,Pole of the Earth. Alfo by apply- 
ing one Pole of a very fnall Piece of Loaddone to the 
fame 
