SPIINOUS FISHES 291 



the ocean ; the sail of the element in which they live noway mixing 

 ivith their constitution. Whence then is it that animals will live only 

 there, and will quickly expire, when carried into fresh water * It may 

 probably arise from the superior weight of the sea water ; as from the 

 great quantity of salt dissolved in its composition, it is much heaviei 

 than fresh water, so it is probable it lies with greater force upon the 

 brgans of respiration, and gives them their proper and necessary play 

 on the other hand, those fish which are used only to fresh water, can- 

 not bear the weight of the saline fluid, and expire, in a manner suf 

 focated in the grossness of the strange element. 



But though there are some tribes that live only in the sea, and others 

 tn fresh water, yet there are some whose organs are equally adapted 

 to either element ; and that spend a part of their season in one, and 

 a part in the other. Thus the salmon, the shad, the smelt, and the 

 flounder, annually quit their native ocean, and come up our rivers to 

 deposit their spawn. This seems the most important business of their 

 lives ; and there is no danger which they will not encounter, even to 

 the surmounting precipices, to find a proper place for the deposition 

 of their future offspring. The salmon, upon these occasions, is seen to 

 ascend rivers five hundred miles from the sea; and to brave not only 

 the danger of various enemies, but also to spring up cataracts as high 

 as a house. As soon as they come to the bottom of the torrent, they 

 seem disappointed to meet the obstruction, and swim some paces 

 back : they then take a view of the danger that lies before them, 

 survey it motionless for some minutes, advance, and again retreat ; 

 till at last summoning up all their force, they take a leap from the 

 bottom, their body straight, and strongly in motion ; and thus most 

 frequently clear every obstruction. It sometimes happens, however, 

 that they want strength to make the leap ; and tlien, in our fisheries, 

 they are taken in their descent. But this is one of the smallest dan- 

 gers that attend these adventuring animals in their progress : num- 

 berless are the methods of taking them; as well by the hook, as by 

 nets, baskets, and other inventions, which it is not our business here 

 to describe. Their capture makes, in several countries, a great 

 article of commerce ; and being cured in several different manners, 

 either by salting, pickling, or drying, they are sent to all the markets 

 of Europe. 



As these mount up the rivers to deposit their spawn, others, par- 

 ticularly the eel, descend the fresh-water stream, as Redi assures us, to 

 bring forth their young in the sea. About the month of August, an- 

 nually, these animals take the opportunity of the most obscure nights 

 and when the rivers are flooded by accidental rains, seek the ocean 

 When they have reached the sea, and produced their young, for they 

 are viviparous, they again ascend the stream at different times, as 

 opportunity offers, or as the season is favourable or tempestuous 

 Their passage begins usually about the end of January, and continues 

 till towards the end of May, when they are taken in the river Arno by 

 millions, and so small that a thousand of them goes to a pound. 

 There is nothing more certain, than that they descend in our own 

 rrvers after floods, in great abundance, and are thus caught in nets, 

 to very great advantage. They are also possessed of a power of 

 dimbing over every obstacle ; for, by applying their glutinous and 



