1873 The Depths of the Sea: An Account of the General Results of the Dredging Cruises of H.M.SS. 'Porcupine' and 'Lightning' During the Summers of 1868, 1869, and 1870, Under the Scientific Direction of Dr. Carpenter, F.R.S., J. Gwyn Jeffreys, F.R.S., and Dr. Wyville Thomson, F.R.S.

Description

First Edition, Illustrated

First edition.

Rebacked, with the original board covers laid down.

Illustrated with seven dual-spread colour maps,  a folding graph and many full-page and in-text figures, eleven of which are vignettes. Collated, complete. 

This work offers a thorough report of the dredging cruises of HMS Lightning and HMS Porcupine in the summers of 1868, 1869 and 1870. Being interested in crinoids, and prompted by the results of the dredgings of Michael Sars in the deep sea off the Norwegian coasts, C. Wyville Thomson persuaded the Royal Navy to grant him use of the steamers. 

Among the results described here is showing that animal life existed down to depths of 650 fathoms, that all marine invertebrate groups are present at this depth, and that deep-sea temperatures are not as constant as had been supposed, but vary considerably, indicating oceanic circulation. 

The Porcupine expedition in particular disproved the azoic theory of Edward Forbes, which hypothesised that life could not exist below 600 m depth due to the pressure.

Written by Scottish natural historian and marine zoologist, C. Wyville Thomson, who is also well-known for serving as the chief scientist on the Challenger expedition of 1872-1876.