( ) 
* In one of the fmall Pipes I or K, juft againft the 
Return of it, which enters the End of the firft-men* 
tioned Glafs Tube at A or B, is a fmall Hole, by 
which to introduce into it fo much Spirit of Wine 
as may fill it from the Middle of the Scale on one 
Hand to the Middle of that on the other $ this Hole 
may be afterwards flopped by a Skrew-pin. 
The inner Ends of the two Halves of the Glafs 
Tube A B (hould be fixed into the entire Part of the 
Brafs Tube D F with a Cement made with old hard 
Bees-Wax, or fome other Materials not dilfolvable by 
Spirit of Wine, as fhould alfo the Ends of the 
fmall Pipes I and K into this and the Tube H : 
Thofe Halves, as to the remaining Part of their 
Lengths) may be faftned down with any ftrong 
Cement. 
This Level may befeton to oneof theLimbs of the 
Quadrant, fitted up for this Purpofe, in the manner 
exprefs’d in the Figure. It hath an Index moveable 
on the Center, and a Spring at the other End to keep 
it fteady, when it is dire&ed to any of the Divifions 
on the Arch, which needs no other Divifion than 
into whole Degrees. The Index may be furnilhed 
either with plain Sights, or may carry a Ihort Tele- 
fcope, with a Vane in its Focus, to receive the Image 
of the Sun, when it is bright enough ^ but if the 
Sun be hazy, or the Moon, or a Star be obferved, a 
Aiding Shutter may be drawn out to tranfmit the 
Rays of Light to the Eye-glafs. The Vane has alfo 
a Thread fix’d on it perpendicular to the Plane of the 
Quadrant. The whole Inftrument ( for the eafier 
managing it) may be fupported by a Staff, refting 
with one End on the Floor. 
Z 
The 
