162 THE POPULAR SCIENCE MONTHLY. 



space, which is probably flat, but which possibly may turn out to be 

 inherently crooked. And now, when somebody shakes his head and 

 proposes to examine whether there is not something wrong with this 

 whole mode of philosophizing, which mistakes crutches for limbs, and 

 scaffolds for buildings, Professor Newcomb hurls a wooden thunder- 

 bolt at him, or a reviewer in the New York " Critic " reminds him 

 that " the sound thinker gives himself little uneasiness respecting the 

 laws of thought." 



Now let us look for a moment at the atom. The physicist or 

 chemist gets it originally as an ancient heir-loom, handed down from 

 the times of Democritus or Lucretius. It is a solid body, with attach- 

 ments of hooks and loops. The modern scientist takes off the attach- 

 ments, and holds on to the main solid body, polishing it for his use. 

 So this body becomes round ; but in course of time appear the miner- 

 alogist and chemist with their morphological laws, such as the law of 

 Mitscherlich, with theories of polarity or valency, or what not ; and to 

 accommodate them it is proclaimed that the atom is a cube or a rhomb 

 or an octahedron, or whatever else will silence the most clamor. After 

 a while, Kroenig or Clausius declares that, in the interest of his kinetic 

 theory of gases, he must insist on the perfect sphericity of the atoms 

 or ultimate molecules ; and thenceforward (for a month at least) they 

 are spherical. But, at the expiration of the month, Maxwell points to 

 certain anomalous facts which are supposed to be inconsistent with 

 atomic sphericity, and he suggests that it be modified so as to give the 

 atoms the form of oblate or prolate spheroids ; and, of course, his sug- 

 gestion is adopted. In a short time some physicist rushes out of his 

 laboratory or study, and announces that he has just obtained experi- 

 mental results or arrived at theoretical conclusions requiring an utter 

 rejection, not only of the definite figure of the atom, but of its entire 

 bulk ; and forthwith it is subtilized into a mere center of force. But 

 now the physicist is reminded that force must have a substratum, and 

 that its indispensable correlate is inertia. At this juncture the pan- 

 geometer flits upon the scene, and offers the perplexed physicist his 

 fourth dimension in which to lodge both the extension and " inten- 

 sion " i. e., mass of the centers of force, assuring him that he may 

 have the mere punctuality of the atom in ordinary space, and behind 

 it, in space of four dimensions, any amount of bulk and weight. At 

 this stage of the proceedings the physicist begins to look desperate ; 

 perhaps he is silently meditating the question, What is to become of 

 experimental research if the properties of things can vanish ad libitum, 

 and retire into the recesses of the pangeometrical regions ? And yet, 

 woe to him who ventures to suggest to the chemist that the origin of 

 the trouble is not in his retorts, but in the sincipital alembic through 

 which all his results are at last distilled, or to show the physicist that 

 there is no defect in the lenses of his microscope, but great want of 

 achromatism in those of his intellect ! He speedily learns that the 



