[ 45 ] 
in or through the chalk, fo deep as to have in it at" 
Ieaft four feet of {landing -water. From the bottom 
of this water fhould arife a piece of leaden pipe, to 
or near the furface of the ground, where it fhould> 
be ftrongly joined to the end of an upright iron bar,., 
an inch and half diameter, faftened to the wall by 
leaden If raps, and extending ten feet above the ridge 
of the building, tapering from the ridge upwards to 
a {harp point, the upper i 2. inches of copper, the 
iron to be painted. 
We mention lead for the- under-ground part of 
the conductor, as lefs liable to ruft in water and moift 
places ; in the form of a pipe, as giving greater ftiff— 
nefs for the fubftance ; and iron for the part above- 
ground, as flronger, and lefs likely to be cut away.. 
The pieces, of which the bar may be compofed,, 
fhould be fere wed ftrongly into each other, by a clofe 
joint, with a thin plate of lead between the fhoul- 
ders, to make the joining or continuation of the metal; 
more perfect. Each rod, in paffing above the ridge, 
fhould be fcrongly and clofely connected by iron or 
lead, or both, with the leaden coping of the roof,, 
whereby a communication of metal' will be made 
between the two bars of each building, for a more 
free and eafy conducting of the lightning into the 
earth. 
We alfo advife, in confideration of the great lengths 
of the buildings, that two wells, of the fame depth; 
with the others, (hould be dug within twelve feet 
of the doors of the two outftde magazines ; that is 
to fay, one of them on the north fide of the north: 
building, the other on the fouth fide of the fouth 
build.— 
