the Residence of certain Fishes. 229 
to hybernate, he might find a dormitory in Loch Lomond or clse- 
where, to pass the chilling hours of a Highland winter. And the 
change would be less than in the case of the land animals; since 
there is not such a difference of temperature in the one case as in 
the other. 
While on this subject, it will not be out of place to mention a 
parallel object of economy, far less known than it merits, and 
indeed little known out of Scotland, where it has been practised, 
although in a very limited manner, for many years. This is the 
preservation of sea fish in salt-water ponds. There are three of 
these in Scotland ; one in Galloway, another in Fife, and the third 
in Orkney. In these, even cod are known to live for many months, 
and to increase in size, without any loss of quality, and without 
any other food than that, imperceptible to us, which is brought by 
the daily influx of the sea, In the pond in Galloway, some in- 
dividual cod have been living for many years, so as to have be- 
come tame, if such a word may be applied to a fish, feeding, like 
hogs, out of a trough when introduced with a supply of food. 
This practice is so obvious an extension, as it is an improvement, 
of the expedient of using well-boats, as to afford cause of surprise 
that it has not been adopted by those who are interested. Motives 
of interest in the proprietors would shortly become matter of ad- 
vantage to the consumers; and the unsteadiness of a fish-market, 
no unimportant object of municipal attention, even in London, 
would cease to be a subject of complaint, 
The Romans, who seem to haye far exceeded us in all that 
relates to eating, as they did in a few other matters, were well 
acquainted with this practice ; and the history of their Vivaria has 
descended to us, with much more that relates to their rural 
economy, of which this formed a distinguished branch. Colu- 
mella says, decidedly, that they transported the spawn of various 
sea fishes to the different fresh-water lakes round Rome, ‘ marinis 
seminibus implebant,” and that this was a regular trade with the 
early agriculturists of the rustic Republic, before the rich and lux- 
urious took the keeping of artificial Vivaria into their own 
hands, He mentions the Mugil, which is probably our mule 
