c 30r A 7 
which ferves to receive the mer- 
cury {fpilt by moving PE vetiels 
in the other Dome, 
id XI. The board (reprefented 
by ¢ in Fig. X.) of the box con- 
taining mercury, reprefented in g 
as it is fixed in the box; and in- 
verted in 4, on purpofe to fee the 
funnel hollowed out in the under- 
side agr--It. 
— cas ig A "dion OF “the b board 
of the box (reprefented by Fig. 7 
c),on purpofe to fhew the form of 
the funnel, and the manner of fix- 
ing this board in the box, by let- 
ting its floping edges in a groove 
cut out in the fubftance of the box, 
fo that the mercury cannot pufh 
it up, but that it may be taken 
out at pleafure. 
Fig. XIIT. 
