energy, will cause an atomic rearrangement in the molecular structure of the weaker substance the susceptible groups of albumin molecules. We can readily understand why this energy may not be sufficient to dissociate and yet be ample to produce a molecular rearrangement in the weaker body. Now, a molecular rearrangement of a substance, say of an homologous group of albumin molecules, may destroy the susceptibility to a given species of bacterium without destroying the nutritive value of the molecules. Molecules thus changed will have been thrown out of harmony, in synchronous molecular vibration, with the species of bacterium to which they had previously been susceptible and can not therefore be transformed into toxins by this species. Somatic immunity, I hold, is a condition of atomic rearrangement of susceptible molecular groups of the organism, so that their susceptibility to a given species of bacterium is more or less permanently destroyed. Since the albumin molecules are susceptible to the micro-organisms because of certain structural similarities held in common by the two, susceptibility will be destroyed and this group of molecules will become immune to the micro-organism when the structural similarities held in common cease to exist. It is understood, of course, that immunity of the albumin molecules carries with it immunity of the organism, and that permanency in duration of one coexists with permanency in the other.

The more permanent duration of protection which usually characterizes the somatic type of immunity, and that which distinguishes this type from that produced by antitoxins, is due to the fact that the atomic rearrangement of albuminoid groups, brought about by reverse wave energy of the toxin, show a marked disposition to permanency.

The contention that atomic rearrangement may be permanent in character is not unsupported by evidence; it is well known that changes in molecular cell structure may be produced artificially and that such changes may be transmitted from parent to progeny through many generations of the cells. I refer to the changes produced in cells by "attenuation." It has been shown that the

capacity of a ferment or pathogenic cell to bring about decomposition changes in susceptible substances, and to produce specific products may be increased or decreased, destroyed or restored, at the will of the operator by exposing such cells to attenuating influences or agents. It has further been made known that the capacity of a cell to produce ferment or infectious products is not a vital capacity, inasmuch as it can be destroyed without doing injury to the cell in its capacity to grow, to assimilate or to propagate itself. Since the capacity of a cell to excite fermentation or pathogenic changes is not a vital capacity, and since this capacity may be variously modified or destroyed by physical agencies, I have argued that the forces concerned are physical, and have pointed out their nature and origin. Now, since the condition of "attenuation" of bacteria and ferment cells is due to atomic rearrangement of cell structure, which may be permanent, and may be transmitted from parent to progeny, and since the changes produced in the plasma and tissue cells of the body by toxins are also atomic rearrangements, the same degree of variation in permanency of acquired structure will apply alike in both cases.

Before concluding this essay, it is but fair that I point out as I see them what may be regarded as weak places in the ferementation theory. The existence of atoms has never been absolutely proved, the atomic theory being accepted as true because it serves to explain and make intelligible chemical phenomena which otherwise would be obscure and inexplicable.

The evidence that atoms (molecules) possess a motion of translation, and that this is the source of radiant heat is almost positive; but the proof that they also possess an interior motion is less conclusive. Many scientists believe, however, that atoms not only have interior motions, but that such motions are primordial and ultimate, and are therefore indestructible. "That the molecule (atom) does not get its interior motion from the heat of dissociation is certain, for on being allowed to recombine, it yields up its transitory activity and with it as many degrees of temperature as disappeared in accomplishing its dissociation. We must not

endow the molecule (atom) wth gratuitous attributes, but it is surely an entity of some kind, having, in the first place, persistent and regulated motion; secondly, it has inertia, or mass, the property of conserving "vis-viva." Thirdly, it has some bond with its fellow, by which the motions of both are modified by constant stress, according to a definite law of distance; and this, following Newton, we call attraction. Fourthly, it has the complex property of interchange of momentum, accompanied by that of conserving and compounding motion by angular rebound upon an infinitely near approach, which we call 'resiliency' or 'repulsion.' It is conceived as having dimensions, figure, polarity, elasticity and harmonic vibration with periods as undeviating as those of the 'Moons of Mars." "

The fermentation theory is based upon the hypothesis, in the absence of positive supporting proof, that the interior motion of atoms are transmitted to the surrounding ether as wave motions of energy just as the translatory waves of atoms are transmitted in the development of ether waves of radiant energy, heat and light. Proof that the interior specific motions of atoms transmit to the ether related vibrations (waves) must rest for the present, as the atomic theory does, upon the competency of this theory to intelligently explain large groups of physical phenomena which otherwise are obscure and inexplicable.

Professor Julius Thompson (Thermo-Chemical Investigation) says: "Theoretical chemistry is based upon the molecular theory, according to which all matter is made up of molecules and these molecules of atoms. The physical state of bodies depends upon the arrangement and motions of the molecules; the other physical and chemical properties depend upon the kind and number of atoms in the molecule, upon their arrangement and relative motions."

Now, this statement as it stands does not convey to the mind how "the number and kinds of atoms in the molecule, their arrangement and relative motions," gives to matter the chemical and physical properties it possesses. The statement is simply one

of fact and is not an explanation of the nature of the forces which bring about the chemical and physical changes referred to. The chemical and physical properties of matter, and the rationale of their action, will become intelligible, however, when it is understood that the latent or potential energy of matter is the sum of energy of its molecular ether waves which become active or kinetic energy, capable of molecular dissociations and reassociations when, under favorable conditions, it is brought in contact with molecular structure whose wave energy bears a definite, required relation to the molecular wave energy of the first.

Michael Foster, in discussing physiological problems, has this to say: "We have, in speaking of protoplasm, used the words 'construction,' 'decomposition' and the like, as if protoplasm were a chemical substance. And it is a chemical substance, in the sense that it arises out of the union or coincidence of factors which can be resolved into what the chemists call 'elements,' and it can be, at any time, by applying the appropriate means, broken up, into the same factors and, indeed, into chemical elements.

"This is not the place to enter into a discussion of the nature of the so-called chemical substances, or, what is the same thing, a discussion concerning the nature of matter; but we may venture to assert that the more these molecular problems of physiology, with which we are now dealing, are studied, the stronger becomes the conviction that the consideration of what we call 'structure' and 'decomposition' must, in harmony with the modern teachings of physics, be approached under the dominant conception of modes and motion.

"The physicists have been led to consider the qualities of things as expressions of internal movements; even more imperative does it seem to us that the biologist should regard the qualities (including structure and composition) of protoplasm as in like manner the expression of internal movements.

"We must not pursue the subject any further here, but we feel it necessary to introduce the caution concerning the word 'substance.' We may repeat the assertion that it seems to us neces

sary for the satisfactory study of the problems on which we have been dwelling, to keep clearly before the mind the conception that the phenomena in question are the result, not of properties of the kinds of matter, in the vulgar sense of the word, but of kinds of motion."

The "kinds of motion" in matter capable of producing "the phenomena in question" are not described by the distinguished physiologist and author whom I have quoted. The motions of atoms and molecules do not, of themselves, satisfy the understanding as such motions alone are incapable of accounting for the energy manifested specifically by matter in its various forms. Something else is needed to make the forces of "construction," "decomposition" and the like intelligible, and this something, I claim, is supplied by the theory that vibrating atoms produce in the ether corresponding vibrations.

2.

BIBLIOGRAPHY.

"Physiological Chemistry."

Jorgenson: "Micro-organisms and Fermentation," 1900.

3. Frankel: "Text-Book of Bacteriology."

4.

5.

"Annals Pasteur Institute," March, April, 1899-October, 1898.
"St. Louis Courier of Medicine," February, 1900.

6. "Deutsche Med. Woch.," 1901.

7. "Comptes Rendus de Soc. Biology," Paris, 1901.

8. "British Medical Journal," 1901.

9. "Deutsche Med. Woch.," 1901.

10. "Annals of Pasteur Institute," October, 1899; June, 1900; September, 1900.

11. "Münchener Med. Woch.," 1901.

12. Erlich and Morgauroth: "Berlin Klin Woch.," 1899, Nos. 1 and 22.

13. Nicole: "Annals Pasteur Institute," 1898. "Societe de Biologic," Paris, 1898.

14. Kraus: "Weimer Klin Woch.," 1897.

15. Meyers: "The Lancet," 1900.

16.

McFarland: "Text-Book of Pathogenic Bacteria."

17. Encyclopedia Britannica, 9th American Edition. Atom.

18. "Study of Natural Philosophy," 1830. "Familiar Letters on Scientific Subjects," 1866.