As a subject, highly important in its relations to maritime œconomy, the history of fish-poison constitutes an interesting branch of naval hygiene; instructions, therefore, for its investigation, ought always to be given to the naturalists and chemists who may be appointed to attend voyages of discovery. The notice of the scientific men who accompanied _Peyrouse_ was officially directed to this important object; but the unhappy fate of that celebrated adventurer rendered the commission fruitless. The obscurity which attends this branch of toxicology has in many cases occasioned a corresponding degree of credulity; and sailors, as well as others, entertain an unfounded prejudice against various fish, that are not only innocuous, but even useful as articles of food. It would, however, appear that those which are harmless in one latitude may prove poisonous in another; it may be stated generally, that fish are more deleterious within the tropics, than in other seas. In torrid regions the softest kinds are the most susceptible of that change which renders them poisonous, and hence the policy of the Hebrew legislator becomes apparent; “_whatsoever has no fins nor scales in the waters, that shall be an abomination unto you._” Levit. c. xi, v. 12, and Deut. cxiv, v. 9, 10. The most complete history of this intricate subject, and of the dissertations to which it has given rise, is to be found in the _Edinburgh Medical and Surgical Journal_,[486] by _Dr. Chisholm_, who has brought together, and cited a great number of authorities, biblical and classical, foreign and domestic, for its illustration. An interesting paper is also published on the same subject in the _Medical Repository_,[487] by _Dr. Burrows_. To the above sources we must beg to refer the reader who is desirous of farther information than can be afforded him by the present work. _Symptoms of Fish-poisoning._ Nausea; thirst; tormina of the bowels; vomiting; an eruption on the skin, resembling the nettle-rash; tumefaction of the face; head-ache; difficult respiration; distention of the abdomen; sometimes _cholera morbus_; vertigo; delirium; cold sweats; convulsions; death. Such is the train of symptoms, liable of course, to variation in the order of succession, which are produced by the ingestion of fish-poison, as occasionally existing in salmon, herrings, eels, mackarel, many of the testaceous and most of the crustaceous fish of this country; and in a great number of fish[488] inhabiting the tropical seas.