. The depths of the sea; an account of the general results of the dredging cruises of SS. 'Porcupine' and 'Lightning' during the summers of 1868, 1869 and 1870, under the scientific direction of Dr. Carpenter, J. Gwyn Jeffreys, and Dr. Wyville Thomson. Porcupine (Ship); Lightning (Ship); Ocean; Marine animals; Deep-sea temperature; Marine sediments. rii.] DEEP-SEA TEMPEEATUBES. 291 water on the outer sliell, and thus protecting the bulb within. Mr. Casella was directed to construct some ther- mometers on this plan, only instead of being filled with air, the outer shell was nearly filled w
. The depths of the sea; an account of the general results of the dredging cruises of SS. 'Porcupine' and 'Lightning' during the summers of 1868, 1869 and 1870, under the scientific direction of Dr. Carpenter, J. Gwyn Jeffreys, and Dr. Wyville Thomson. Porcupine (Ship); Lightning (Ship); Ocean; Marine animals; Deep-sea temperature; Marine sediments. rii.] DEEP-SEA TEMPEEATUBES. 291 water on the outer sliell, and thus protecting the bulb within. Mr. Casella was directed to construct some ther- mometers on this plan, only instead of being filled with air, the outer shell was nearly filled with alcohol warmed to expel a portion of the remaining air, and the chamber was then her- metically sealed, leaving a bell of air and vapour of alcohol to yield to the pressure and relieve the bulb within. The ' Miller - Casella ' thermometer proved so nearly perfection that it was decided to adopt it in future, and to use it as a standard in a series of experiments which were undertaken to test the ordinary Six's thermo- meters of the Hydrographic Office pattern. We depended upon this thermometer alone in our subsequent cruises in the ' Porcupine,' and we found it most satisfactory. During the summer of 1869 temperature observa- tions were taken at upAvards of ninety stations, at depths varying from 10 to 2,435 fathoms. Two thermometers, numbered 100 and 103 respectively, were sent down at every station, and in no instance did they give the least reason to doubt their accuracy. Every observation was taken by Captain Calver himself, the lead with the thermometers attached being in every single instance let down by his own hand, u 2. Fir,. f,:!.-TlK' Millcr- Casolla iiiodifiuation of Six's self-regis- tering theriuonieter. The large bulb is double, with a layer of liquid and a bell of vaiiour between the shells, to relieve Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appeara
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectmar, booksubjectocean
