THE WORLD OF ATOMS.
The infinite groups of atoms flying through all time and space, in different directions and under different laws, have interchangeably tried and exhibited every possible mode of rencounter: sometimes repelled from each other by concussion; and sometimes adhering to each other from their own jagged or pointed construction, or from the casual interstices which two or more connected atoms must produce, and which may be just adapted to those of other figures,—as globular, oval, or square. Hence the origin of compound and visible bodies; hence the origin of large masses of matter; hence, eventually, the origin of the world.—Dr. Good’s Book of Nature.
The great Epicurus speculated on “the plastic nature” of atoms, and attributed to this nature the power they possess of arranging themselves into symmetric forms. Modern philosophers satisfy themselves with attraction; and reasoning from analogy, imagine that each atom has a polar system.—Hunt’s Poetry of Science.
MINUTE ATOMS OF THE ELEMENTS: DIVISIBILITY OF MATTER.
So minute are the parts of the elementary bodies in their ultimate state of division, in which condition they are usually termed atoms, as to elude all our powers of inspection, even when aided by the most powerful microscopes. Who can see the particles of gold in a solution of that metal in aqua regia, or those of common salt when dissolved in water? Dr. Thomas Thomson has estimated the bulk of an ultimate particle or atom of lead as less than 1/888492000000000th of a cubic inch, and concludes that its weight cannot exceed the 1/310000000000th of a grain.
This curious calculation was made by Dr. Thomson, in order to show to what degree Matter could be divided, and still be sensible to the eye. He dissolved a grain of nitrate of lead in 500,000 grains of water, and passed through the solution a current of sulphuretted hydrogen; when the whole liquid became sensibly discoloured. Now, a grain of water may be regarded as being almost equal to a drop of that liquid, and a drop may be easily spread out so as to cover a square inch of surface. But under an ordinary microscope the millionth of a square inch may be distinguished by the eye. The water, therefore, could be divided into 500,000,000,000 parts. But the lead in a grain of nitrate of lead weighs 0·62 of a grain; an atom of lead, accordingly, cannot weigh more than 1/810000000000th of a grain; while the atom of sulphur, which in combination with the lead rendered it visible, could not weigh more than 1/2015000000000, that is, the two-billionth part of a grain.—Professor Low; Jameson’s Journal, No. 106.
WEIGHT OF AIR.
Air can be so rarefied that the contents of a cubic foot shall not weigh the tenth part of a grain: if a quantity that would fill a space the hundredth part of an inch in diameter be separated from the rest, the air will still be found there, and we may reasonably conceive that there may be several particles present, though the weight is less than the seventeen-hundred-millionth of a grain.
DURATION OF THE PYRAMID.
The great reason of the duration of the pyramid above all other forms is, that it is most fitted to resist the force of gravitation. Thus the Pyramids of Egypt are the oldest monuments in the world.