730 
ICHTHYOLOGY. 
to perfection ; an advantage which nature has not granted 
to fome birds and beafts, which will not breed out of their 
own climes. 
We have already had inftances of fifh being conveyed 
from one river to another, or from a river to a lake, and 
vice vcrfa. This method has been employed with fuccefs 
in Germany in regard to the fhad, with which ponds and 
pieces of ltagnant but clear water, with a bottom of fand 
and gravel, preferred by the fhad to all other, have been 
ftocked. In the year 1779 , Dr. Bloch wrote from Berlin 
that this experiment had been attended with complete 
fuccefs. It is not above fifty years ago that Mr. Copland 
conveyed perch into the Ken-loch and the river Urr, 
where they have thriven remarkably well; and has been 
the cafe with the trout, taken from the river Leven and 
depofited into Loch Long, in the county of Renfrew. 
The carp, which is a fifh peculiar to warm climates, has 
been fuccefsfully introduced into the rivers and ponds of 
Pruflia, Denmark, and England. Linnaeus fays poiitively 
that this fifh formerly was not known in Sweden ; and it 
is ftill unknown in Livonia, unlefs it has been conveyed 
thither within thefe few years. The frefh-water gourami 
in the Ifle of France, where it has multiplied prodigioufly, 
came originally from Bengal. It was M. Poivre, that 
philofophic adminiftrator, who had the honour of enrich¬ 
ing the rivers of this ifland with a fifh which in goodnefs 
and fhape may be compared to the fhad. That fmall fifh, 
the brilliant gold and filver colours of which all admire, 
the Chinefe dorado, was brought to Europe from the 
northern part of China. If fo much was done for a ufe- 
lefs fifh, valued merely on account of its fhining fcales, 
by making it traverfe the feas to embellifh, in compliance 
with fafhion, our halls and our cabinets, why fhould we 
not do the fame to obtain fifh ufeful to man, which would 
recompenfe our troubles and our facrifices ? The Romans, 
fated with victories and triumphs, received from tributary 
Afia the rarefl fpecies of fifh to make a figure on their 
tables at their feafts. What the Romans did for the lux¬ 
ury of the rich, let us do for the general good, for the 
utility of the poor; and let us diftribute to every river the 
beneficent germs of a new fecundity, which will double 
their productions and their produce. 
A fecond method of multiplying the number and.quan- 
tity of the natural productions of rivers, would be, to 
convey into the frefli waters thofe fifh produced in fait wa¬ 
ter. N.aure herfelf gives us examples, and we have no¬ 
thing to fear if we take her as our guide. Fifh originally 
produced in fait water, have voluntarily eftablifhed them- 
felves in frefii, where they have loft all remembrance of 
the tumult of the waves amidtt which thofe of their fpe- 
cies play and fport. Several lakes of Scotland poffefs fal- 
mon, which, abandoning their erratic ftate for a calm 
and fettled life, have there become gradually naturalized. 
The lalmon of the rivers Cluden and Nitli, as well as 
thofe of the Dee, are evidently indigenous, as is proved 
by their external form. The fturgeon, the fterlet, and 
different kinds of faimon, which Pallas obferved in the 
Kama, refide there, according to this, naturalift, without 
interruption, and never defeend to the Cafpian fea. This 
celebrated traveller found the fea-dog in the lake of Bai¬ 
kal, though it is never caught in the Eniffei nor in the 
lower Angora. He fuppofes, indeed, that it has been 
conveyed into that lake in confequence of fome confider- 
able variation in the level of the globe, or by fome other 
extraordinary event. On one hand, we fee the foudre, a 
falt-water lilh, inhabit at prefent the Seine, and lofe itfelf 
in the banks of Toumidoes, twenty-four miles above 
Rouen: on the other, Liancourt found the herring in the 
Elk, Potowmack, Hudfon’s river, and the Delaware, ri¬ 
vers of North America; and, according to Twifs, the lame 
fifh is caught in the frefh-water lakes of Ireland j it is 
found in prodigious fhoals’in the bafons of Loch Lomond 
and Loch Eck, in Scotland : it afeends alio the river Forth 
aiong with the 'iiilmon, and even to a very great diilance 
from the fea. In Pruflia, it has been feen in the Oder* 
in the environs of Stettin, at the diftance of more than 
ninety miles from the mouth of that river; and we are told 
by the fifners of Mark and Eackhuyfen, that the herring is 
found in the river Vollenhoven on the other fide of the 
Zuyder Zee, efpecially towards the end of the fifhing fea- 
fon. There is no doubt, that thefe different falt-water 
fifh might be eafily naturalized in frefli water; and that 
the cale would be the fame in regard to many other fpe- 
cies, if proper care were taken, after their removal, to be¬ 
llow on them that attention neceffary to enfure fuccefs 
to the experiment. We have a proof of this in the ponds 
of Eaft Friefland. The large plaice, tranfported thither 
from the North Sea, have multiplied by myriads; and they 
now people thofe pieces of water which before were to¬ 
tally unproductive. While encouraged by thofe examples*, 
is there any reafon to doubt of fuccefs ? “ Every mare 
who catches a fifh,” fays Dr. Franklin, “draws from the 
water a piece of money.” Let not the maxims and ex¬ 
ample of this philofopher be loft to pofterity ; let them 
rather produce fruit, like ftrong and vigorous feed fown ire 
a fertile foil. The method uled fuccefsfully by the doc¬ 
tor for making herrings frequent a place they had never 
been in before lias been mentioned under the article Clu- 
pea, vol. iv. p. 689. But the herring is not the only 
fifh that might be naturalized in frefli water ; we might 
add feveral fpecies of the PleuroneCtes, luch as the brill* 
the barbel, and other flat-fifh, which, pofleffing traits of 
the flounder family, have alfo fimilar wants and habits : 
alfo the mullet, the goby, the whiting, the gar-fifh, and 
perhaps one or two fpecies of the gurnet. See the article 
Fishery, vol. vii. p. 406. 
But to fucceed in tranfporting or conveying fifh, atten¬ 
tion muft be paid to whether they love brifk or ftill wa¬ 
ters; whether they are 11 fed to a bottom of marl, ftone* 
clay, or weeds. In general, molt fifh delight in great depth 
of water, where there are fprings or running waters ire 
different direftions, and where the bottom is diverfified 
with fand, clay, and weeds. Lakes or ponds with fteep. 
fliores or banks are not fo proper to receive fifh newly 
brought as thofe where the fhore is fhallow and even; for 
the height of the banks prevents the rays of the fun from 
reaching the bottom with fufficient force to hatch the 
eggs. But they may even be put into fuch lakes as thefe* 
provided you conftruct refervoirs of wood near the banks; 
thefe fhould be large, flat, and uncovered ; the fide-planks 
fhould be fo fixed that they may be removed after Spawn¬ 
ing time ; the fides and bottom fhould be furniflied with 
branches of fir or deal, again ft which the fifties may rub 
themfelves and depofit their eggs. 
Tile moft favourable time for tranfporting fifli is juft 
as they are ready to fpawn. If you would breed feveral 
fpecies at the fame time, each fpecies fhould have a par¬ 
ticular relervoir, where they lhould have room in, propor¬ 
tion to their fize and number. After fpawning take the 
fifh out of the pond with a net, and put them elfewhere. 
Then alfo the branches of trees are to be taken away, to 
expofe the eggs or fpawn as much as pofiible to the fun. 
By this means ufefui or fcarce fifh of diftant countries 
may be propagated in great numbers. 
There is yet another method of attaining this objefh. 
Soon after fpawning-time, gather up the weeds, plants, 
and ftones, on which the fifh have depofited their eggs, 
and take them elfewhere to be hatched : fifli have even 
been brought to life in a room by thefe means. See 
P- 745- 
It is not only in deep ponds with fntooth fhores that 
newly-tranfported fifli may be put; thick and troubled wa¬ 
ters will an fiver very well for tench and carp. Regard muft 
alfo be had to the feafon in tranfporting fifh : fpring and au¬ 
tumn are the beft; in finnmer the heat, as well as ftorms 
that may arife, often kill them. It is alfo to be confidered 
what fpecies of fifh you would tranfport, and the nature of 
them; thole that are hardy and tenacious of life, as the eel, 
that 
