Forty-feet Reflecting Telescope. 405 
the speculum carriage, which must now be brought into a 
proper position for rolling up. When this is done, the carriage 
is to be tied to the axle of the point of support, A B, fig'. 34. 
and by turning the bar-machine handle, the speculum with 
its carriage will be drawn up to the foundation beams E E, 
A A, fig. 3. which are 16 inches above the foundation wall. 
By the time that the carriage comes near to the top, there 
will be room for six 3-inch planks that are provided, to be laid 
one after another upon the rolling beams rs, which will form 
a platform of 5 feet 10 inches by 5 feet 3, for the reception of 
the carriage. But these planks must not be put down till the 
telescope has been first brought back, and fixed again close to 
the carriage, which must be sustained in its place while this is 
doing. Then, advancing again, the platform is laid down, 
board by board, till completed, while at the same time the 
carriage will be drawn upon it. 
As soon as that is safely landed, a strong rope is to be 
hooked into a loop, fixed upon the beam at a, fig. 15. This 
going down to a pulley with a swivel hook at the bottom, 
which is put through one of the three handles of the speculum, 
returns to a pulley hung upon the hook b. From that pulley 
it goes forward to a leading pulley at V 7 , upon the foundation 
timber, fig. 3. This directs the end of the rope to the barrel, 
which serves for the great round motion of the whole tele- 
scope. When the handle of that machine is moved, the spe- 
culum will be lifted up in its carriage, which being eased, 
must now be turned about while the mirror is yet partly rest- 
ing upon it, so as to become parallel with the back of the tube, 
and close to it. As soon as the mirror is fairly suspended, the 
carriage must be unbolted, and drawn sideways from under it. 
mdccxcv. 3G 
