136 Notices respecting New Books. 
aud it should pass down in as direct a line as possible, and pe- 
netrate several feet below the foundation, from which it should 
be inclined outward, The underground part of the conductor 
is better formed of copper, to prevent its decay; it should be 
connected, if it possibly can, with a moist stratum of earth or 
with alarge body of water. The penetration of the conductor 
to some depth below the level of the foundation, will in many 
instances procure this advantage for it. The conductor is some- 
times made wholly of copper, it may then be thinner than if 
made of iron: for a stationary conductor, I should conceive that 
a copper rod of half an inch thick would answer every required 
purpose ; and there is little doubt that a less quantity of metal 
made into a hollow tube so as to increase its superficies would 
be equally or even more effectual. Conductors for ships have 
been made of chains (which are highly improper) and of cop- 
per wires which are easily attached : ‘but they are with equal 
ease detached ; and I have been informed by several captains, 
that in many ships furnished with such conductors, they are kept 
in an inactive state packed up below during long and hazardous 
voyages. For this reason it would be better that fixed con- 
ductors should be employed; they might I should conceive be 
attached to the mast, and where motion is required an inter- 
ruption should be made in the inflexible conductor, and its parts 
be connected together by a length of spiral wire, which would 
be at once perfectly continuous, and sufficiently flexible to yield 
to every necessary movenient.” 
Conductors for ships will be much more effectual if they are - 
connected with a strip of metal surrounding the deck, and con- 
tinued to the copper-bottom. Carriages which are usually fil- 
leted round with metal for ornament, may be rendered very se- 
cure if these strips are connected with each other, and continued 
over every edge, so as to surround the prominences of the carriage ~ 
completely, a metallic communication being continued from them 
to the ground. Inthe open air Mr, Singer advises that shelter be 
not patil heneath a high tree, or building, but considers a di- 
stance of twenty or thirty feet from them as rather an eligible 
situation. He particularly insists on, the necessity of avoiding 
every approach to large masses of water, and even to the stream- 
lets which may have resulted from a recent shower ; for they are 
all excellent conductors, and lil kely to determine the direction of 
the explosion. Ina house, the partial conductors which usually 
determine the course of the discharge are for the most part the. 
appendages of the walls and partitions; the most secure situa- 
ton, therefore, is the middle of the room; and this may be ren- 
dered more so, by standing on a glass-legged stool, a mattress, 
pr even a thick woollen hearth-rug. The middle story is the 
most 
