S48 Report of the Committee 
of the pot and it. Thefe methods of making the cover 
fiiut clofe can be ufed more conveniently when the cover 
is made to enter within the pot, as in the figure, than 
when it goes on on the outfide. 
There are various eafy ways by which the hole in the 
cover, through which the tube of the thermometer is 
paired, may be flopped up, and by which the thermome- 
ter may he fufpended at the proper height. The hole in 
the cover may be flopped up by a cork, which muft firfl 
have a hole bored through it, big enough to receive the 
tube, and be then cut into two, parallel to the length of the 
hole. Another method, more convenient in ufe, but not 
fo eaiily made, is reprefented in fig. 6. which exhibits a 
perfpe£live view of the apparatus ; a a is the cover; h the 
hole through which the thermometer is paffed ; b b a fiat 
piece of brafs fixed upon the cover; and D(/e« a Aiding 
piece of brafs, made fo as either to cover the hole h, or 
to leave it uncovered as in the figure, and to be tightened 
in either pofition by the fcrew s Aiding in the Ait m m ; 
a femi-circular notch being made in the edge b Z>, and alfo 
in the edge d d, to inclofe the tube of the thermometer : 
pieces of woollen cloth fiiould alfo be fattened to the 
edges b b and d d, and alfo to the bottom of the Aiding 
piece p d'E e, unlefs that piece and the cover are made fuf- 
ficiently flat, to prevent the efcape of the fleam. In 
order 
