These are insects, according to Linnaeus, of the class aptera, and genus oniscus. It comprehendeth fifteen species. One species is the wood louse, and the variety employed is of a bluish colour, which, if touched, rolls itself up in a rounded form. They are found under stones and logs of wood, in cold, moist places; and the pale brown, and the bluish black sorts are indiscriminately used. Those found in vaults are said to contain the largest proportion of salts, and most esteemed.
The London college directs them to be dried by suspending them in a thin canvas bag, placed within a covered vessel, and over the steam of hot proof spirits, that, being killed by the vapour, they may become friable.
The taste of these insects is sharp and pungent, and they are supposed to possess an alkaline quality,"and to be diuretic.
They are prescribed, both fresh and dry, in hepatic, and other visceral obstructions; in pituitous diseases of the chest, and suppression of urine; the dose in powder, from Э i. to 3 i; in an expressed vinous infusion, ij. repeatedly. They have been swallowed alive in great numbers daily; and though reckoned diuretic, the effects usually attributed to them are doubtful. From fifty to one hundred are eaten alive; or infused in wine and pressed, half an ounce is taken for a dose.