tion, though the author had drawn that instrument only to justify the dissolution of the British Empire, and as a justification of these States in setting up a new form of government for themselves. Jefferson planted the seed, and this revolutionary document led to a great civil war as much as any one paper can be said to cause any great act in any great nation; and 4,000,000 of negroes broke their chains to look up to the Declaration and Lincoln's Proclamation as the basis of their freedom, and which are now incorporated into the Constitution by the XIIIth Amendment, and their rights as men are therewith forever secured to them. ART. V.-1. On the Structure of the Simple Tissues of the Human Body. By LIONEL S. BEALE. London. 1861. 2. Uber die Nerven und das Blut in ihrem gesunden und Krankhaften Zustande. (On the Nerves and the Blood in their sound and diseased conditions.) Freiburg. 1830. 3. Protoplasm; or, Life, Force, and Matter. By LIONEL S. BEALE. London. 1870. 4. Icones Histologicæ. Von KöLLIKER. Leipsic. 1864. 5. Vom Bau des thierischen Körpers. (Of the Fabric of Animal Bodies.) F. LEYDIG. Tubingen. 1864. 6. Uber die Ubereinstimmung in der Structur der Thiere und Pflanzen. (On the Agreement in the Structure of Animals and Vegetables.) Schwann. Berlin. 1839. It is the purpose of this paper to give a condensed résumé of the origin, progress, and present condition of the CellTheory, in the first place, and to indicate its leading relations to the biological group of sciences, in the second. That important modifications of the current doctrines of physiology, VOL. XXX.-NO. LX. 7 psychology, pathology, and medical science, must ultimately accrue from the microscopic scrutiny of tissues which has been in progress during the last two centuries, though brought to comparative perfection only with the last twenty-five years, has been long conceded, not only by scientific men, but by thoughtful workers in every department of life. It would, however, be overstating the prospect very materially to intimate, as some enthusiasts have, that the final definition of matter, except in Aristotle's view of the case, will ever be accomplished through the agency of the microscope; for the highest power of Beck's best binocular instrument, 10,000 diameters, or 1,000,000,000 areas, to be multiplied by 50,000 in the matter of diameters, or by 2,500,000,000 in the matter of areas, the primitive atom, if that interesting subject of speculation may be regarded as having an entity at all, would scarcely be revealed-a consideration that shows the utter hopelessness of penetrating to the very beginnings of life by any miracle of microscopy that the optician will ever be able to furnish, the practical limits of the instrument having already been pretty nearly attained. It is quite true, nevertheless, that a proximate analysis of living tissues has been obtained, and that, while non-nucleated cells exist exist as the lowest forms and the primordial starting-point of animal life, in the general evolution of complex organisms, whether animal or vegetable or participating in qualities common to both, the nucleated cell is not only a special starting-point of all really organic structures, but that the structure is evolved and grows by means of the primordial cell reproducing itself, undergoing various modifications as connective, muscular, osseous, or nervous tissue, and thus building up a complex organism and a complex series of functions, all of which, as special forms of life, are derivative from one primordial form. The impassable partition that formerly existed between the different types of tissue has thus been broken down, with material advantage, no doubt, to enlightened views of the origin and special determining causes of variations in function, and cer tainly with material advantage to the study of morbid function, whether presented in the form of physical or of mental disorder for diseases are in ultimate analysis but perverted cell-activities, with a consequent tendency to disintegration and death. Thus, for example, in tuberculosis, whether pulmonary, renal, or cerebral, the deposited tubercle results either from the nucleation and multiplication of masses of germinal matter (protoplasm) which have exuded through the capillary walls from the blood and set up an existence as morbid tissue, or from nuclei, or germinal centres, in connection with the capillary walls in a case of tubercle of the pia mater (envelope of the brain) Dr. Beale* reports that the deposits were connected with the vascular walls, and that the nuclei of the cells were unquestionably implicated in their origin, if not directly responsible for them. Dr. H. C. Bastian,† the great exponent of the spontaneous generation theory, and Dr. Comil, both eminent microscopists, with some differences in the manner of expressing it, substantially support this opinion. Again, in pneumonia, the so-called exudation, or morbid product that fills up the vesicular portion of the lung, usually considered as the result of a proliferation of the connective-tissue corpuscle, is rather the result of a proliferation of minute particles of germinal matter (considerably smaller than the white blood corpuscles) that have passed out through the capillary walls with the liquor sanguinis-a phenomenon which, by the way, occurs in all inflammatory processes and fevers to a greater or less extent. The common white corpuscle of suppuration originates in the same way, as any reader may observe for himself, by producing a slight superficial abrasion on his finger, and observing it for several hours under a power of from 300 to 500 diameters. First a hyaline liquid appears on the surface of the abrasion; but, in the course of three * Microscope in Clinical Medicine. London, 1867, p. 166. + Tubercular Meningitis. Edinburgh Medical Journal, volume for 1867, p. 875. Tubercle in connection with the vessels. 1868. hours, the period depending somewhat on temperament, minute granules make their appearance, and gradually grow larger and larger until they resemble the white blood corpuscles. These cells have movement and life in the hyaline plasma in the same manner as the normal white corpuscles in the circulation have, and contribute in a similar manner to the formation of new tissue in the place of that destroyed by the abrasion. The suppuration corpuscle is, indeed, identical with the leucocytes of the blood, and the hyaline liquid that first exuded was blood plasma, which percolated through the damaged walls of the numerous capillaries, disarranged and broken up in the process of bruising, the finest of which were not more than .001 millimetre in diameter, but yet performed a definite office in plasmic circulation. In cancer, on the other hand, the acute histologist discerns one of the results of the excessive multiplication and perversion of germinal matter, consequent upon the appropriation of an excess of nutrient pabulum; while in cirrhosis, with its shrinking or hardening or wasting, diminished nutrition is indicated, but this diminution may occur either as the exponent of defective nutrition in general, or as the exponent of a growing impermeability of the septum, or cell wall, through which it must pass in order to be appropriated as pabulum by the interior fluid contents of the cell. So, also, the excessive appropriation of pabulum may result from excessive permeability of the septum or from the nature of the fluids in which the cell is bathed. Suppuration of the tissue known as epithelium, which is very abundant in germinal matter, furnishes a familiar illustration of this phenomenon. As the result of an excess of pabulum, the cells send out buds or processes with greater rapidity than they can be converted into formed matter on the surface, so as to constitute proper tissue-cells, and these undeveloped cells become the white corpuscles of the suppuration that inevitably ensues. Hence, there is no simpler form under which pure protoplasm can be studied than that known even to the uninitiated eye as the white matter of suppuration, which is generally present in inflam matory processes of all types. In contrast with these phenomena, fatty degeneration presents a series of examples of the transformation of the cell-contents from the state of germinal matter into the non-vital product known as fat, the septum or cell-wall constituting the external membrane of the vesicle, which, however, is still in a condition to be reabsorbed as nutriment. How to bring about this necessary reabsorption is thus the great and complex (generally hopeless and baffling) problem with which the physician has to deal in treating cases of fatty degeneration whether of the strictly organic or of the nervous structure. But on these points it is enough to say, once for all, that, in all instances whatsoever of morbid function or of pathological transformation, the medical man is confronted with perverted cell-activities, and may trace the disorder, whatever its type, to this one source. It would be very unsafe to assert, however, as some with a flavor of quackery have done, that this perversion is not very frequently one of the results of habitual perversion of function, continued until the devitalizing process has set in, and consequent morbid nutrition, local or general, has followed; for it is undoubtedly true that the contagia of numerous diseases are such from the fact that they perpetuate their processes when introduced into a healthy organism, and induce as the result of their incubation a perverted cell-activity, either local or general; and it is very likely that the contagion itself consists, in most instances, of minute particles of morbific germinal matter swimming in the atmosphere-not as the specific germs of specific diseases, as Dr. Tyndall's theory presupposes, but as ordinary germinal matter from bodies in which perversion has been once set up, and capable of perpetuating and multiplying itself and the morbific agency whence it sprung. This is a general view, and one to which there are many special exceptions. Estival catarrh (hay-fever) is, for example, due to the action of the pollen of flowering plants, grasses included, which in contact with membranes absorb moisture, develop and expel a granular |