Atoms—It is not derogatory to the human mind to say that it can neither comprehend great things nor small It is a fact, that no man krows what an atom is ; that is, an atom of any material in its smallest state of exist ence Very few can comprehend the size of the earth we inhabit, or of the sun, or of the planet Jupiter, which immense orbs are but a collection of atoms, and which, after all, are only a few of the countless worlds of the universe We can conceive the existence of a small particle of marble, or of wood, or of sugar, or paper ; but when the mind endeavors to form a conception of the smallest particle of any of these materials, it falters When again it considers that what appears to be the smallest particle of sugar or of marble can be further divided, and that, in reality, these materials consist of three other atoms of matter united to form one particle or atom of sugar, marble, amp;c, the idea is perplexing It is an ascertained fact, that sugar consists of carbon, oxygen, and hydrogen ; but the ultimate size of the atoms of any of these elements is beyond the mind's comprehension Nevertheless, chemists give to atoms of all the elements an ultimatum, and assign to them a definite weight—that is, a weight by comparision of one to another It is found that when one substance unites with another, it does so always in a definite regular proportion ; thus one hundred parts of oxygen always unite with double their weight of sulphur, four times their weight of selenium, and eight times their weight of tellurium, and so on with every other element, sometimes higher in weight, and at others lower, as the case may be; but it never varies for each specific element Hence, after numerous experiments performed with the greatest care, chemists have fixed an atomic weight to all the elements, which is the proportion with which they combine with each other ; though of different weight, yet they are atom to atom SEPTIMUS PIESSE