for adjujling i thermometers . 849 
order to keep the thermometer fulpended at the proper 
height, a clip may be ufed like that reprefented in fig. 7 . 
which by the fcrew s mull be made to embrace the tube 
tightly, and may reft on the cover. That part of the 
clip which is intended to bear againft the tube, had belt 
be lined with woollen cloth, which will make it ftick 
tighter to the tube, and with lets danger of breaking it. 
Another method, which is rather more convenient, when 
the top of the tube of the thermometer is bent into a 
right angle, in the manner frequently pradtifed at prefent 
for the fake of more conveniently fixing it to the fcale, is 
reprefented in the fame figure ; G v y f / is a plate of brafs, 
Handing perpendicularly on the cover, and l/n/z a piece 
of brafs, bent at bottom into the form of a loop, with a 
notch in it, fo as to receive the tube of the thermometer, 
and to fuffer the bent part to reft on the bottom of the 
loop; this piece muft Hide in a flit k£, cut in the plate 
l/nzz, and be tightened at any height by the fcrew t. 
4thly, It is beft making the water boil pretty brifklv, as 
otherwife the thermometer is apt to be a great while be- 
fore it acquires its full heat, efpecially if the veflel is very 
deep. The obferver too flrould w r ait at leaft one or two 
minutes after the thermometer appears to be ftationary, 
before he concludes that it has acquired its full height. 
Vol. LXVIL 5 O sthly, 
