264 Scientific Intelligence, 
bismuth; a like pole, at right angles to it, formed a re- entering angie 
an thers a weak pole of magnetic action was caused; iron was at- 
tracted from it to the prominent: corners ; bismuth moved up a it; 
th nd 
put with their longer edges together, rents a lengthened chamber 
with two entrances; and a little needle being carried in at either en- 
trance passed rapidly through spaces of weaker and weaker force, and 
found a part in the middle where magnetic action was not sensible, 
Other very interesting results were obtained by making chambers in 
the polar extremities of electro-magnets. A cylinder magnet, w 
core was 1°5 inches in diameter, had a concentric cylindrical chamber 
formed in the end, 0°7 in iameter, and 1-3 inches deep. When iron 
lings were brought near this excited pole, rea clung around the out- 
ca r 
edge, When they were a placed inside on a card they were 
and so on to a long bar, were brought into contact with the same point 
at the bottom of the inverted chamber, though the filing could not be 
held by attraction, nor the smaller pieces of iron, yet as soon as those 
were employed which reached to the level of the chamber mouth, . 
beyond it, attraction manifested itself; and with the larger pieces 
rose so high that a bar of some pounds weight could ms hel agus 
their removal, then take up some other ee or exist without action: 
the 
s never been shown or even suspected; the second is et 
imposs ibility, being i ietciokaelll with the observation of force. But! 
the oe of a sing ames ‘are thrown upon each other, and . 
rce Senet or other) is not affected oe 
power on other magnets, or ae left to 
: al disposition of the force. is'so ict so 
right lines through the magnet does not ¢ d 
ces, whilst the force in external (and necessarily) curve 
