Having folded it in this manner, they place it with
an interjacent Pastboard into an hot Press, where it is kept very violently
prest, till it be dry and stiff; by which means, the wales of either
contiguous sides leave their own impressions upon each other, as is very
manifest by the second Figure, where 'tis obvious enough, that the wale of
the piece ABCD runs parallel between the pricked lines ef, ef, ef, and as
manifest to discern the impressions upon these wales, left by those that
were prest upon them, which lying not exactly parallel with them, but a
little athwart them, as is denoted by the lines of, oooo, gh, gh, gh,
between which the other wales did lie parallel; they are so variously, and
irregularly creas'd that being put into that shape when wet, and kept so
till they be drie, they so let each others threads, that the Moldings
remain almost as long as the Stuff lasts.
Hence it may appear to any one that attentively considers the Figure, why
the parts of the wale a, a, a, a, a, a, should appear bright; and why the
parts b, b, b, b, b, b, b, should appear shadowed, or dark; why some, as d,
d, d, d, d, d, should appear partly light, and partly dark: the varieties
of which reflections and shadows are the only cause of the appearance of
watering in Silks, or any other kind of Stuffs.
From the variety of reflection, may also be deduc'd the cause why a small
breez or gale of wind ruffling the surface of a smooth water, makes it
appear black; as also, on the other side, why the smoothing or burnishing
the surface of whitened Silver makes it look black; and multitudes of other
phaenomena might hereby be solv'd, which are too many to be here insisted
on.
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