RL =< ee. CUCU 
ENGINEERING SKILL OF SPIDERS. 217 
the distance of the web (counterpoise?) from the ground was about a 
metre and a half, which would seem to preclude the theory that it had 
been raised up from the ground by the elasticity of the web, or the 
mechanical impact of the wind, 
Nevertheless, I am constrained to believe that in this case also the 
explanation of intentional engineering must be dismissed. The pellet 
had evidently been separated from the vault by the erosion 
nate ,, of the atmosphere, and had either been lifted up from the 
ee ground, where it had fallen, in the manner I have described, 
or, which is more probable, it had entangled within the web 
as it fell; had been prevented by the foundation cords from dropping 
entirely to the ground; had been held above the surface by the viscidity 
and natural elasticity of the threads; and while thus hanging, accidentally 
poised, it was made use of by the spider as a point from which to re- 
attach her foundation line. As long as it remained in poise, undisturbed 
by the wind or passing objects, it would be available for the purpose 
of staying her web; and in this position it was the fortune of Professor 
Parona to see it. 
However this theory may accord with the facts, I am perfectly assured 
that the spider could not have cut off from the vault a particle of soil so 
large, and then have transferred it to the position where it was seen. 
Such action is so wholly foreign from all that I have observed of the 
habits of Orbweavers, that I cannot possibly allow myself to admit it as a 
reasonable explanation. On the whole, my judgment is that none of the 
instances heretofore observed, in the form at least in which they are re- 
corded, afford sufficient testimony to permit us to believe that Orbweavers. 
have the engineering ability to counterpoise their webs against the action 
of wind and the natural shrinkage of the web material, by means of peb- 
bles or other objects attached to marginal lines. 
Indeed, if such action were really proved, it would seem to me an un- 
wise and not a cunning exception to the general habit in like web sites, 
which is to carry the principal supporting line quite down to the firm 
earth. Nothing could be gained, and much would be lost, by exchanging 
this for an unstable counterpoise. Would the spider be apt to pause 
within an inch or two of the ground, which was thus clearly within its 
reach, to make so unprofitable an exchange? The only special 
wisdom that can be allowed the spider in the case is that 
which accepts an undesirable situation as at least available, and 
adapts her spinningwork thereto; and that is certainly to be rec- 
ognized, and it is sufficiently remarkable. 
UE 
Counter- 
poising 
Useless. 
It is not to be doubted that spiders do show considerable powers of 
adaptation in adjusting their spinningwork both to peculiar situations and 
~ “| ost ot Dine 
