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In the sixth case, where the sense is hindered by the too great power of the object, reduction is made either, 1. by removing the object farther from the organ of sense; or, 2. taking off from its force by the interposition of such a medium as may weaken, but not annihilate it; or, 3. by admitting and receiving the reflexion of the object, where the direct force of it is too strong, as by receiving the reflexion of the sun in a bason of water." The seventh case of concealment from the senses, (viz. that wherein the sense is so full charged with the object, as to leave no room for the admission of a new one) is almost wholly confined to the sense of smelling, and odours, and does not considerably regard the subject in hand. So that thus much may suffice for the business of reducing insensible things to such as are sensible. Sometimes also reduction is made, not to the sense of man, but to the sense of other creatures, whose sensations, in some particulars, exceed those of men, as the sensation of a hound, in some kinds of smell, and the sensations of a cat, an owl, &c. which see things in the night by the latent light of the air, which is not externally

varum; and Sir Isaac Newton's Optics, and Principia, passim. - o-o. 7

illuminated. For Telesius has justly observed that, there is a certain original light in the air itself, though small, faint, and generally unserviceable, with regard to the eyes of men, and many other creatures; because the animals to whose sense this light is proportioned can see by night, which it is not so probable they should do without light, or by an internal light of their own”. It must here be observed, that we treat only of the failures and insufficiencies of the senses, and the remedies thereof; for the deceptions of the senses should be referred to the particular enquiries of sense and sensibility t, excepting only that grand fallacy of the senses, in making the measure and rule of things correspond to man; and not to the universe, which is an error that cannot be corrected, but by reason and universal philosophy [. 41. Among our prerogative instances, we assign the eighteenth place to journeying instances, which we also term instances of the road, and sometimes jointed instances; that is, such as indicate the motions of nature, gradually continued or connected. But the instances of

* * See the Author's Table of Enquiry for the History of

Light and Splendor.

** f See De Augment. Scientiar; and the Sylva Sylvarum. # See Part I. Aph. 42, &c.

this kind rather escape the observation than the sense. And, indeed the negligence of men is . here surprizing, for they contemplate nature only by fits and starts, or periodically; and then too it is after bodies are complete and finished, and not in their process, or whilst the operation is in hand. But if any man desired to consider and examine the contrivances and industry of a certain artificer, he would not be content to view only the rude materials of the workman, and then immediately the finished work, but covet to be present whilst the artist prosecutes his labour, and exercises his skill. And the like course should be taken in the works of nature. For example; if any one would enquire into the vegetation of plants, he should have an eye from the first sowing of the seed, and examine it almost every day, by taking or plucking up a seed after it had remained for one, two, or three days in the ground; to observe with diligence, (1.) when, and in what manner, the seed begins to swell, grow plump, and be filled, or become turgid, as it were, with spirit, (2) Next, how it bursts the skin, and strikes its fibres with some tendency upwards, unless, the earth be very stubborn: (3.) How it shoots its fibres, in part, to constitute roots downwards; in part, to form stems upwards; and sometimes creep

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ing sideways, if it there find the earth more open, pervious, and yielding, with many particulars of the same kind *.

And the like should be done as to eggs during their hatching, where the whole process of vivification, and organization might be easily viewed; and what becomes of the yolk, what of the whitet, &c. Understand the same of creatures bred from putrefaction; for as to perfect, terrestrial animals, it is somewhat inhumane to enquire into them, by cutting the foetus out of the uterus, unless when opportunity offers by death, abortions, the fortune of the chace, &c. A watch, therefore, is by all means to be kept upon nature, as she is better discovered by night than by dayt, for these contemplations and enquiries may be called nocturnal, by reason of the smallness, or durability, or slow-burning of the watch-light here set up.

The same is also to be attempted in inanimate bodies; and this we have endeavoured af

* See Dr. Grew's Anatomy of Plants, as also that of Mal pighi, and several Pieces to the same purpose in the Philosophical Transactions, French Memoirs, &c." * See Harvey, Highmore, Malpighi, &c. upon this subject. o of Wiz.:Where she is removed from human sight, as she is

in these grand Works, the Formation of Wegetables, Ani+:--> mals, and Minerals.

ter by observing the ways wherein liquors open themselves by fire; for water opens one way, wine another, vinegar another, verjuice another; and milk, oil, &c. with a still greater difference; as may easily be perceived by boiling them over a soft fire, in a glass vessel". But these things are here touched lightly; the place for treating them more exactly and fully being when we come to enquire into the latent process of thingst; for it must be all along remembered, that we do not, at present, treat things themselves, but barely produce examples. 42. In the nineteenth place come supplemental instances, or instances of substitution, which we also call instances of refuge; that is, such as afford information where the senses perfectly fail us, so that we have recourse to them when the proper instances cannot be had. This substitution is procured two ways, viz. either by approximation, or by analogy. For example; there is no medium found, that can possibly exclude the operation of the loadstone in moving iron; not gold, not silver, stone, glass, wood, water, oil, cloth, air, flame, &c.

* See this subject prosecuted in the Author's History of Condensation and Rarifaction.

* See the Author's History of Condensation and Rarifaction throughout.

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