16: Instances of the Lamp

³⁸ There are 5 classes of instances of the lamp, or of immediate information.

These assist the senses.

Every interpretation of nature sets out from the senses, and leads, by a regular fixed and well-established road, from the perceptions of the senses to those of the understanding (which are true notions and axioms).

It necessarily follows that in proportion as the representatives or ministerings of the senses are more abundant and accurate, everything else must be more easy and successful.

The five sets of instances of the lamp are:

1. Those that strengthen, enlarge, and correct the immediate operations of the senses
2. Those that reduce to the sphere of the senses such matters as are beyond it
3. Those that indicate the continued process or series of such things and motions, as for the most part are only observed in their termination, or in periods
4. Those that supply the absolute wants of the senses
5. Those that excite their attention and observation, and at the same time limit the subtilty of things. We will now proceed to speak of them singly.

16. The instances of the door or gate

³⁹ These assist the immediate action of the senses.

Sight holds the first rank among the senses, with regard to information, for which reason we must seek principally helps for that sense.

These helps appear to be threefold:

1. To enable it to perceive objects not naturally seen
2. To see them from a greater distance
3. To see them more accurately and distinctly.

We have an example of the first (not to speak of spectacles and the like, which only correct and remove the infirmity[213] of a deficient sight, and therefore give no further information) in the lately invented microscopes, which exhibit the latent and invisible minutiæ of substances, and their hidden formation and motion, by wonderfully increasing their apparent magnitude.

By their assistance we behold with astonishment the accurate form and outline of a flea, moss, and animalculæ, as well as their previously invisible color and motion.

An apparently straight line, drawn with a pen or pencil, is discovered by such a microscope to be very uneven and curved.

This is because neither the motion of the hand, when assisted by a ruler, nor the impression of ink or color, are really regular, although the irregularities are so minute as not to be perceptible without the assistance of the microscope.

As is usual in new and wonderful discoveries, men have added a superstitious remark that the microscope sheds:

• a lustre on the works of nature
• dishonor on those of art

This means that the tissue of nature is much more delicate than that of art.

The microscope is only of use for minute objects.

If Democritus had seen it, would have exulted in the thought of seeing his atom, which he affirmed to be entirely invisible.

But the inadequacy of these microscopes, for the observation of any but the most minute bodies, and even of those if parts of a larger body, destroys their utility.

If the invention could be extended to greater bodies, or the minute parts of greater bodies, so that a piece of cloth would appear like a net, and the latent minutiæ and irregularities of gems, liquids, urine, blood, wounds, and many other things could be rendered visible, the greatest advantage would be derived.

We have an instance of the second kind in the telescope, developed of Galileo.

By the assistance of which a nearer intercourse may be opened (as by boats or vessels) between ourselves and the heavenly objects.

For by its aid we are assured that the Milky Way is but a knot or constellation of small stars, clearly defined and separate, which the ancients only conjectured to be the case; whence it appears to be capable of demonstration, that the spaces of the planetary orbits (as they are termed) are not quite destitute of other stars, but that the heaven begins to glitter with stars before we arrive at the starry sphere, although they may be too small to be visible without the telescope.

By the telescope, also, we can behold the revolutions of smaller stars round Jupiter, whence it may be conjectured that there are several centres of motion among the stars. By its assistance, also, the irregularity of light and shade on the moon’s surface is more clearly observed and determined, so as to allow of a sort of selenography.[136] By the telescope we see the spots in the sun, and other similar phenomena; all of which are most noble discoveries, as far as credit can be safely given to demonstrations of this nature, which are on this account very suspicious, namely, that experiment stops at these few, and nothing further has yet been discovered by the same method, among objects equally worthy of consideration.

We have instances of the third kind in measuring-rods, astrolabes, and the like, which do not enlarge, but correct and guide the sight. If there be other instances which assist[215] the other senses in their immediate and individual action, yet if they add nothing further to their information they are not apposite to our present purpose, and we have therefore said nothing of them.