so8 Dr. Marcet on the specific gravity and temperature, &c. 
a scale of paste-board is fixed to it, in order to record the re- 
sults of the experiment. 
The bulb and neck being then entirely filled with sea water, 
and the tube fitted on, the fluid is thereby forced up into it to 
a certain height, which is marked on the scale. The bulb is 
now enveloped in cotton-wool, or any other bad conductor, 
and placed in a small jar, and this jar is immersed into a cool- 
ing mixture. The fluid is soon seen descending in the tube 
in proportion as the thermometer descends ; and the gradual 
condensations of the water in the latter part of the experiment, 
such as they really occurred, may be seen marked on the 
scale. The level of the fluid in the tube is represented oppo- 
site No. 2 6, 25, 24,, and 23, at which temperatures it remains 
stationary ; and it then possesses the greatest specific density 
which sea water can attain. 
