357 
Forty-feet Reflecting Telescope. 
ladder $ a %'• 7- with its back £ o n (not expressed in the 
figure) bolted to it, was laid down edgeways, with the ends $ 
and | opposite to the same letters in fig. 3. and the centre Q 
towards the west. In this situation the ends were properly 
secured to the foundation beams, that they might not slip. 
The centre 9 was then raised up to about 10 or 12 feet from 
the ground, and a tackle was fastened on one side to the cross- 
ing of the ladders at i, and on the other, about 2 feet from the 
ground, to a tree at a convenient distance in the east. By as- 
sisting a little at first, in lifting the centre, our tackle soon got 
hold of the ladders, and drew them up. A rope had been pro- 
vided to prevent their going farther than the perpendicular ; 
and being secured in that position, the tackle was now fast- 
ened to the other ladder at ; but instead of making use again 
of our tree, the corresponding tackle was secured on the top of 
the first ladder at 64 by which means we easily drew up the 
second. Both sets of ladders stood now upon the ground, 
within the frame, and with the front legs, oc ( 3 y nearly 
opposite to the same letters on the front beam ; while the legs 
of the back stood opposite the letters \pv J on on the back 
beam. 
We now proceeded to put on the middle top cross-beam, 
which is placed above the two sets of ladders in the angle 
made by their crossing each other. It is expressed by points 
in fig. 7. and may be seen in its place, fig. 1. The method of 
keeping it there, and securing the proper distance of the lad- 
ders by this beam, which is of a cylindrical form, is as follows: 
twelve iron loops, shaped to the ends of the ladders, with arms 
to them like lamp-irons, and a hole at the end of each arm, are 
slipped down upon the ends of the ladders, till two and two of 
mdccxcv. 3 A 
