6o ST. J AGO, 
species of mackerel (the Scomber pelamis, known to sailors 
by the Portugueze name of Bonetta, and the Thijnnus or 
tunny, usually called Albecor). These are both considered 
as esculent, but they have a strong and disagreeable flavour, 
are very dry and black, and dangerous effects are sometimes 
said to have been produced from eating too freely of them. 
The tunny caught in the Mediterranean, was commonly used 
at the feasts of the Romans ; yet they entertained an idea 
that, under certain circumstances, it was poisonous. The 
velocity with which the bonetta and albecor dart across the 
bows of a ship, when sailing at the rate of eight or nine mile& 
an hour, is almost incredible ; it is so rapid that the eye is 
no more able to follow them than it can trace a flash of 
lightning. 
The astonishing velocity, which fishes are capable of exert- 
ing in so dense a medium as Avater, seems to be owing rather 
to their muscular poAver than to any assistance they derive 
from their fins, beyond that of directing their course. A strong 
instance of this fact may be remarked in the amazing height to 
which a salmon will leap through the midst of a water-fall, and 
which he accomplishes more by an effort of muscular strength, 
than by the action of his pectoral fins, the spreading of 
which indeed would tend to retard rather than accelerate his 
progress. But there are instances, still more extraordinary 
than the salmon-leap, .of the astonishing power which the 
nmscles of fishes are capable of exerting ; so very extraordinary 
mdeed, that were they not authenticated in such a manner 
as not to lea\'e the possibility of a doubt, they would cer- 
tainly be considered as the inventions of voyagers. Ships' 
T 
