Hydra weight-detaching sounder for collecting small samples from the sea bottom, of the type designed by Mr Gibbs, Artificer aboard the sounding ship HMS Hydra, 1868, and used in sounding operations in the Atlantic and Indian Oceans. Hydra sounders were also employed by naturalists Charles Wyville Thomson, William Benjamin Carpenter and J Gwyn Jeffreys on HMS Porcupine in investigations of deep sea life in 1869. Hydra weight-detaching sounder for collecting small samples from the sea bottom 1868
Detaching-weight sounder, possibly early form, designed by Ensign Brooke of the US Navy, USA, 1855-1860. Detaching-weight sounder, or ‘Brooke’s Rod’, designed by Ensign Brooke 1855-1860