22 
ANIMAL LIFE ON THE 
minutes. When the threads are thrown out from the 
. conduit they appear in a somewhat slack and unfinished 
state, but this is very quickly and marvellously rectified. 
As soon as the number of threads required at the time 
are set down, the foot is completely withdrawn within, and, 
in sailor fashion, the slackened gear is speedily hove taut, 
and the heaving is as perceptibly accomplished as the action 
of a set of tars upon a tackle fall. 
The strength of a single filament is surprising, being 
capable of bearing in atmospheric pressure the strain of 
five times the weight of a matured mollusc. 
The byssus in some species is long and of a very fine 
texture, capable of being woven into cloth. This is the 
case with a particular species that inhabits the Mediterra- 
nean, but the fabric is only to be found occasionally, and 
sold as a curiosity. 
In our cold northern waters the mussel takes from 
twelve to eighteen months to come to maturity; and its 
well-known tendency in the choice of the most open and 
exposed situations is simply an instinctive provision of the 
creator's, in guiding it to where it can procure its food in the 
greatest abundance. 
Living upon the numerous little particles of animal 
matter that everywhere float about the sea where a sweeping 
tideway exists, it loves to set down its perpetual anchor 
fixings, and, slightly opening its valves, sets in motion its 
wonderful fishing implements, which we will hereafter 
endeavour to describe, and thus procures its food and feasts 
upon its prey at will. The mussel is one of the most 
common, yet the most useful, of all our molluscs. By some 
it is used in the making of an excellent sauce ; others, after 
washing well in fresh water, to free it from sand, and boiling 
in the usual fashion, make of it a savoury fry for an 
