ore we venture to write whole
_Sentences_, or to draw large _Pictures_. And in _Physical_ Enquiries, we
must endevour to follow Nature in the more _plain_ and _easie_ ways she
treads in the most _simple_ and _uncompounded bodies_, to trace her steps,
and be acquainted with her manner of walking there, before we venture our
selves into the multitude of _meanders_ she has in _bodies of a more
complicated_ nature; lest, being unable to distinguish and judge of our
way, we quickly lose both _Nature_ our Guide, and _our selves_ too, and are
left to wander in the _labyrinth_ of groundless opinions; wanting both
_judgment_, that _light_, and _experience_, that _clew_, which should
direct our proceedings.
We will begin these our Inquiries therefore with the Observations of Bodies
of the most _simple nature_ first, and so gradually proceed to those of a
more _compounded_ one. In prosecution of which method, we shall begin with
a _Physical point_; of which kind the _Point of a Needle_ is commonly
reckon'd for one; and is indeed, for the most part, made so sharp, that the
naked eye cannot distinguish any parts of it: It very easily pierces, and
makes its way through all kind of bodies softer then it self: But if view'd
with a very good _Microscope_, we may find that the _top_ of a Needle
(though as to the sense very _sharp_) appears a _broad_, _blunt,_ and very
_irregular_ end; not resembling a Cone, as is imagin'd, but onely a piece
of a tapering body, with a great part of the top remov'd, or deficient. The
Points of Pins are yet more blunt, and the Points of the most curious
Mathematical Instruments do very seldome arrive at so great a sharpness;
how much therefore can be built upon demonstrations made onely by the
productions of the Ruler and Compasses, he will be better able to consider
that shall but view those _points_ and _lines_ with a _Microscope_.
Now though this point be commonly accounted the sharpest (whence when we
would express the sharpness of a point the most _superlatively_, we say, As
sharp as a Needle) yet the _Microscope_ can afford us hundreds of Instances
of Points many thousand times sharper: such as those of the _hairs_, and
_bristles_, and _claws_ of multitudes of _Insects_; the _thorns_, or
_crooks_, or _hairs_ of _leaves_, and other small vegetables; nay, the ends
of the _stiriae_ or small _parallelipipeds_ of _Amianthus_, and _alumen
plumosum_; of many of which, though the Points are so sharp as not t
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