302 NATURAL HISTORY 
arrangement is the securing 
of greater strength to the 
thread, for it is well known 
in rope-making that, in cords 
of equal thickness, those 
which are composed of many 
smaller cords are stronger 
than those which are spun 
at once. Another advant- 
| age still is, that these minute 
| threadlets can be Lies at- 
li HHI] tached to an ob- 
HAA Wii nT Vi) ||| ject than a single : 
HSE AT thread. When 
Fig. 235, fitness cae coming ae the Spider Taeicae 
an attachment of his thread, he presses the spin- 
nerets against the spot selected, and thus fast- 
ens the ends of the threadlets projecting from 
the holes over quite a space. This is seen in 
Fig. 236, which represents an attachment of 
this kind, as seen with the microscope. 
514, The foot of a Spider, a magnified view of which 
is given in Fig. 237, 
has three claws, one 
of which acts as a 
sort of thumb, and 
the others are tooth- 
: : ed as a comb. It is 
Fig. £37.—Triple-clawed Foot of a Spider, mag- supposed that these 
ars combs are used in 
preventing tangling of the threads in the web, and also 
in removing any particles that may become attached to 
it. When a Spider has let itself down from any place 
by its thread, if it goes up again upon it, it gathers up 
the thread into a ball with its claws and throws it away. 
So, also, if any part of its web is rendered useless by any 
thing which becomes attached to it, it is separated from 
Fig. 236. 
