12 
INTRODUCTION. 
contact, and viscid matter is emitted from the papillae; they are then separated by a lateral 
motion, which extends the viscid matter into fine filaments connecting the papillae; on these 
filaments the current impinges, drawing them out to a length which is regulated by the will of 
the animal, and on the mammuhe being again brought together, the filaments coalesce and 
form a compound line. 
Many intelligent naturalists entertain the opinion that spiders can forcibly propel or dart 
out lines from the spinners; but when placed on twigs set upright in glass vessels with per¬ 
pendicular sides, containing a quantity of water sufficient to immerse their bases completely, 
all the efforts they make to effect an escape uniformly prove unavailing in a still atmosphere. 
However, should the individuals thus insulated be exposed to a current of air, either naturally 
or artificially produced, they immediately turn the abdomen in the direction of the breeze, and 
emit from the spinners a little of their viscid secretion, which being carried out in a line by 
the current becomes connected with some object in the vicinity, and affords them the means 
of regaining their liberty. If due precaution be used in conducting this experiment, it plainly 
demonstrates that spiders are utterly incapable of darting lines from their spinners, as they 
cannot possibly escape from their confinement on the twigs in situations where the air is 
undisturbed, but in the agitated atmosphere of an inhabited room they accomplish their object 
without difficulty. Similar means are frequently employed by spiders in their natural haunts 
for the purposes of changing their situation and fixing the foundations of their snares. 
The webs named gossamer are composed of lines spun by spiders, which, on being 
brought into contact by the mechanical action of gentle airs, adhere together, till by continual 
additions they are accumulated into irregular white flakes and masses of considerable magnitude. 
Occasionally spiders may be found on gossamer webs after an ascending current of rarefied 
air has separated them from the objects to which they were attached, and has raised them 
into the atmosphere ; but as they never make use of them intentionally in the performance of 
their aeronautic expeditions, it must always be regarded as a fortuitous circumstance. 1 
M. Bon, a Frenchman, and M. Tremeyer, a Spaniard, have succeeded in fabricating 
stockings, gloves, purses and other articles, of the silk produced by spiders ; but the great 
voracity of these animals, and the difficulty experienced in providing them with food, have 
hitherto prevented this material from being made available for manufacturing purposes on an 
extensive scale. 
1 ‘ Transactions of the Linnean Society/ vol. xv, pp. 449-459. ( Researches in Zoology/ pp. 
229-252. 
l.» -him -i li um i i . mi ll 
mmmm 
