Page:Micrographia - or some physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries thereupon.djvu/306

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Micrographia.

is very hot, but they are nothing so eager of hunting as they are in Italy.

There are multitudes of other sorts of Spiders, whose eyes, and most other parts and properties, are so exceedingly different both from those I have describ'd, and from one another, that it would be almost endless, at least too long for my present Essay, to describe them, as some with six eyes, plac'd in quite another order; others with eight eyes; others with fewer, and some with more. They all seem to be creatures of prey, and to feed on other small Insects, but their ways of catching them seem very differing: the Shepherd Spider by running on his prey; the Hunting Spider by leaping on it, other sorts weave Nets, or Cobwebs, whereby they ensnare them, Nature having both fitted them with materials and tools, and taught them how to work and weave their Nets, and to lie perdue, and to watch diligently to run on any Fly, as soon as ever entangled.

Their thread or web seems to be spun out of some viscous kind of excrement, lying in their belly, which, though soft when drawn out, is, presently by reason of its smallness, hardned and dried by the ambient Air. Examining several of which with my Microscope, I found them to appear much like white Hors-hair, or some such transparent horny substance, and to be of very differing magnitudes; some appearing as bigg as a Pigg's brisle, others equal to a Horss-hair; other no bigger then a man's hair; others yet smaller and finer. I observ'd further, that the radiating chords of the web were much bigger, and smoother then those that were woven round, which seem'd smaller, and all over knotted or pearl'd, with small transparent Globules, not unlike small Crystal Beads or seed Pearls, thin strung on a Clew of Silk; which, whether they were so spun by the Spider, or by the adventitious moisture of a fogg (which I have observ'd to cover all these filaments with such Crystalline Beads) I will not now dispute.

These threads were some of them so small, that I could very plainly, with the Microscope, discover the same consecutions of colours as in a Prisme, and they seem'd to proceed from the same cause with those colours which I have already describ'd in thin plated bodies.

Much resembling a Cobweb, or a confus'd lock of these Cylinders, is a certain white substance which, after a fogg, may be observ'd to fly up and down the Air; catching several of these, and examining them with my Microscope, I found them to be much of the same form, looking most like to a flake of Worsted prepar'd to be spun, though by what means they should be generated, or produc'd, is not easily imagined: they were of the same weight, or very little heavier then the Air; and 'tis not unlikely, but that those great white clouds, that appear all the Summer time, may be of the same substance.

Observ.