118 PHILOSOPHICAL TRANSACTIONS. [aNNO 1673. 



flesh, and sucking the blood of the said fish. It is about 4 inches long; its 

 belly white, cartilaginous, and transparent ; without eyes or head, that could be 

 observed, but instead of a head, it had a hollow snout, encompassed with a very 

 hard membrane, differing in colour and substance from the belly; which snout 

 it thrusts into the body of the fish, as strongly as an augur is wound into a piece 

 of wood, and fills it full of blood to the very orifice. It has a tail shaped .like a 

 feather, serving for its motion ; and under it, two filaments or slender fibres, 

 longer than the whole insect, by which it seems to cling about stones or 

 herbs, and stick the closer in the body of the sword-fish ; attacking those 

 parts only, where the fins of the fish cannot touch or trouble it. Within its 

 belly he observed some vessels, like small guts, reaching from one end of it to 

 the other, which by the pressure of his nail he made reach to the orifice of the 

 snout, whence they retired back of themselves to their natural situation. They 

 seem to be the instruments for sucking the blood, because the snout is in itself 

 an empty part, destitute of fibres and valves to draw and suck with ; whereas 

 these vessels have a motion resembling that of a pump, in which the snout of 

 this animal serves for a sucker, drawing the blood from one end to the other: 

 and the belly of this insect being framed ring-wise, this structure serves to 

 thrust the said inner vessels into the orifice of the trunk, and to draw them back 

 again. As it torments the swordfish, so is itself infested by another insect, 

 which he calls a louse, of an ash colour, fastened towards the tail of this leech, 

 as firmly as a sea snail is to a rock. It is of the size of a pea, and has an open- 

 ing, whence come out many small winding and hairy threads. 



Fourthly, a parcel of sal ammoniac, brought from Sicily, where it had been 

 gathered in the late fiery eruption of Mount -^tna, found on the surface of 

 that ferruginous matter, which remained of the burnt minerals. Some of this 

 salt was as yellow as saffron; some like citron-colour; some white, and some 

 greenish. This seemed to be a factitious salt, such as is sold in shops, being a 

 concrete of nitre, sulphur and vitriol burnt and sublimed, and not pre-existing 

 in those caverns; adding some of this sal ammoniac to pulverised sulphur and 

 nitre, he found, that it was so far from being kindled by fire, that it manifestly 

 hindered the ascension of the brimstone and salt-petre, which were even extin- 

 guished by it, as if water had been poured on them. 



Lumv adjixas Jlppuhus, Derhice j4nno \QjA. Ohservahiles, ah Ephemeride Doct, 

 D. Heckeri deducti, et hrevihus notis descripti, c) J. Flamsteed. N° 99, p. 6162. 

 Not now sufficiently interesting to be reprinted. 



An Account of some Boohs. N° 99, p. 61 66. 

 I. Pharmaceutice Rationalis, sive Diatriba de Medicamentorum Operationibus 



