ders of the heavens were concealed from us beyond the powers of the naked eye; and astronomy, that exalted science, which illustrates the omnipotence of the Divine Creator of the universe more eminently than any other branch of human knowledge, has been improved, and brought, by this simple instrument, to a degree of perfection unthought of in former ages. The discovery was owing to chance rather than reflection, as it is certain that the theory upon which it depends, was not known when the first telescopes were made. Several claimed the honour of the invention; but Galileo, in the beginning of the seventeenth century, having been told of a certain optic glass made in Holland, which brought distant objects nearer to the eye, considered by what means this effect could be produced; and grinding two pieces of glass into form, as well as he could, fitted them to the ends of an organ-pipe, and with this indifferent apparatus, showed at once the novelty and wonder of the invention, to the Venetian noblesse, on the top of the tower of St. Mark. From this time Galileo devoted himself wholly

to the improving and perfecting of the telescope, and, by his perseverance, deserved the honour, usually attributed to him, of being the inventor of the instrument, and of its receiv ing the denomination of Galileo's tube, from his name. The Doge of Venice rewarded his assiduity with the ducal letters, and doubled his salary.

MRS. HARCOURT. The extraordinary talents of this great man, improved the first invention of the telescope to a vast degree of perfection; but it has been reserved for the period in which we live, to advance the magnifying powers to a height at once truly astonishing. Our cotemporary, Dr. Herschel, made surprising progress in celestial geography, if I may be allowed the expression, by means of his Newtonian seven-feet reflector, the most powerful instrument of the kind ever seen. It enabled him to discover many stars before unknown, and curious particulars relative to those with which we were previously acquainted.

CHARLES. When the immense and inconceivable distances of the fixed stars are considered, it is wonderful to reflect that the in

ventive powers of such a diminutive animal as man, have ever attained to such degrees of information, on a subject apparently so far beyond his reach.

HENRY. I do not think that the stars are so very far distant. On a clear night I have observed them but a little way above my head. I have tried several times to count them, but they are so numerous, that I have always found it impossible.

CHARLES. You are much deceived, my dear brother, in both respects. The stars that are visible to the naked eye are not so numerous as we are apt to suppose, from viewing them in a confused, irregular manner. A thousand is supposed to be the greatest number ever seen in our hemisphere at one time, by the keenest eye and most attentive observer. Their extreme distance conceals them from our sight, except they are unveiled by the assistance of telescopes; for they are really numerous, beyond our limited imagination to conceive: and in order to give you a faint idea of their vast distance, I will relate a few observations that I have

heard upon the subject. Nothing, that we know, is so swift in its passage as light. A ray of light passes from the sun to the earth in eight minutes and thirteen seconds, a distance of ninety-five millions one hundred and twenty-three thousand miles; and yet, though possessing this amazing velocity, it would be one year and a quarter traversing the space between us and the nearest fixed star. A cannon-ball, discharged from a twenty-four pounder, with two-thirds of its weight of powder, moves at about the rate of nineteen miles in a minute, but would be seven hundred and sixty thousand years passing from the nearest fixed star to our earth. Sound, which travels at the rate of nearly thirteen miles in a minute, would be one million one hundred and twenty thousand years in passing through the same space.

CECILIA. How far does the structure of the universe, viewed in this light, exceed the bounds of the strongest imagination! Well might David express his sense of those wonders, by exclaiming, that "the Heavens declare the glory of God, and the firmament showeth his handy work."

SOPHIA. Addison remarks, that the universe is the work of infinite power, prompted by infinite goodness, having an infinite space to exert itself in; so that our imagination can set no limits to it.

MRS. HARCOURT. The microscope is an instrument calculated to show the other extreme of nature's works, by magnifying very. minute objects, so as to render that clear to the sight, which, from its minuteness, was before imperceptible. Dr. Hooke, who has written on the microscope, divides the objects proper to be viewed by it, into three classes, which he calls exceedingly small bodies, exceedingly small pores, and exceedingly small motions. Small bodies must either be the parts of larger bodies, or things the whole of which is too minute for our observation, unassisted by art: such as small seeds, insects, salts, sands, &c. Very small pores are the interstices between the solid parts of bodies, as in stones, timbers, minerals, shells, &c. or the mouths of minute vessels in vegetables; or the pores in the skin, bones, and other parts of animals. Extremely small motions are the

VOL. 11.


« VorigeDoorgaan »