10 
Sir Humphry Davy on the 
south poles on the north side; and that those placed over, had 
their south poles turned to the south, and their north poles 
turned to the north ; and this was the case whatever was 
the inclination of the needles to the horizon. On breaking 
the connection, all the steel needles that were on the wire in 
a transverse direction retained their magnetism, which was as 
powerful as ever, whilst those which were parallel to the 
silver wire appeared to lose it at the same time as the wire 
itself. 
I attached small longitudinal portions of wires of platinum, 
silver, tin, iron, and steel, in tranverse directions, to a wire of 
platinum that was placed in the circuit of the same battery. 
The steel and the iron wire immediately acquired poles in the 
same manner as in the last experiment ; the other wires seemed 
to have no effect, except in acting merely as parts of the 
electrical circuit ; the steel retained its magnetism as power- 
fully after the circuit was broken as before ; the iron wire im- 
mediately lost a part of its polarity, and in a very short time 
the whole of it. 
The battery was placed in different directions as to the 
poles of the earth ; but the effect was uniformly the same. 
All needles placed transversely under the communicating 
wires, the positive end being on the right hand, had their 
north poles turned towards the face of the operator, and those 
above the wire their south poles ; and on turning the wire 
round to the other side of the battery, it being in a longi- 
tudinal direction, and marking the side of the wire, the same 
side was always found to possess the same magnetism ; so 
that in all arrangements of needles transversely round the 
wire, all the needles above had north and south poles oppo- 
