The bioplasmic germ theory of disease of Dr. Beale has not received at the hands of many the favorable attention which it deserves. It will be proper to give some notion of the distinguished author's views, and chiefly in his own words. In his work called Disease Germs he says: "Vegetable germs are found in the tissues during life in a state of health—•on the mucous membrane of the mouth, they invade the tissues and the intestines, but the living germinal matter of the tissues is probably perfectly free from vegetable germs." " In very many different forms of disease these bacteria germs, and probably of many fungi, are to be discovered in the fluids of the body. but the evidence yet adduced does not establish any connection between the germs and the morbid pro cess." "Germs, apparently of the same nature as those of cholera, are invariably to be found in the old epithelial cells in the mouths of healthy persons, and not rarely in those from many other surfaces. In the intestinal canal, in various slight derange ments, they are common enough, so that we cannot but conclude that their presence is due, rather to alterations in the fluids consequent upon morbid changes, than that they are themselves the cause of the disease. They follow the morbid change instead of preceding it;" and it is his opinion that bacteria germs grow and multiply whenever a condition in the animal system favors the production of A nahulum suitable for their development, "From the fact that bacteria grow and multiply, not only in a few special fevers, but in a great variety of different morbid conditions, it is evident that they have nothing to do with any peculiar form of disease." In a chapter discussing " some difficulties which pre rent us from accepting the vegetable germ theory of disease," Dr. Beale says: "If contagious diseases are due to the entrance into the organism of such minute vegetable germs as those described, is it not wonderful that we escape disease? Minute vegetable germs, resembling those to which contagious diseases have been attributed, are everywhere, though they may easily escape observation. If. however, the pabulum adapted for them he present, and the conditions favorable to their develop ment exist, they soon grow and multiply, and abundant evidence is afforded of their presence." Explaining the nature of disease germs, as he conceives them to be, he says: " I consider it to be almost certain that the material of which these particles are composed has the power of forming matter like itself from pabulum around it, which differs from it in properties and composition. Such living germs may pass from the organism on which they grow to another, and will grow and multiply there if they meet with the proper pabulum." "Upon the whole, then, I venture to conclude that the millions of contagious particles produced in the organism in an eminently contagious disease are all the direct descendants of the very few, or perhaps even, the single particle first introduced; just as the millions of bacteria and fungi developed in certain decomposing organic matters in the course of a few hours may have been produced from one, or at most, a very few particles." It must be admitted that these statements, coming as they do from a microscopist of long experience, and who uses, with consum mate skill, lense$ haying a magnifying poWer of 5,000 diameters, .deserve the most respectful consideration.. It appears to be admitted on all hands that some diseases appear to be generated by inoculation with fluids in which the highest powers of the microscope fail to reveal any organisms whatever, and that in other cases all that can be seen is granular matter, so minute in its particles that their form cannot be made out; and yet, in view of the fact that specific diseases, exhibiting well marked patho logical characteristics,' are produced by such fluids, it must be held that some definite organism is present, and surely such organism must be regarded as a germ. Dr. Beale says that fungoid matter is found within bioplasmic cells. Why, then, may not fungoid cells growing iu certain localities contain within themselves certain poison, obtained from the soil in which they grow, capable, when introduced into the animal organism, of producing disease, the vegetable cell acting merely as a carrier? From the investigations of Drs. Klebs of Prague, and Tommasi of Rome,..it appears that a certain form of fungus generates fever and ague, and it also appears that another kind of vegetable organism, discovered by Dr. Salisbury of Cleveland, O., has the power of generating the same disease. If these are not identical plants how can their action be explained unless it be supposed that, although the plants differ, they contain the same contagious or disease-producing principles? But Dr. Salisbury has found in the same locality plants of different species which produce, in his opinion, intermittent fever (q.v.). Is it not, therefore, probable, in view of all the facts which have been col lected by competent investigators in all parts of the world, that vegetable spores are often the carriers of diseas germs? It is well known that vegetables which have been grown with manure; containing quantities of undecomposed feculent matter; are capable, when eaten, of producing disease. Why, then, may not fungi flourishing in localities infected by animals or men,-contain within them disease germs which have either been preserved in the soil, or have multiplied from generation to generation? In the feu or morass, disease germs probably remain undecomposed an indefinite period of time if they are far enough beneath the surface, and covered with water. When the shrubbery is cleared away and the surface becomes dry, they spring into activity and generate disease. They may be deeply buried in the earth, and even be hidden in the seams of rocks, and remain harmless until an excavation for a railroad or for building brings them to the surface, where the conditions favorable for their growth exist. The opinion is held by many learned and practical physicians that drinking water obtained from swamps or any localities where the soil contains the poison of malaria, is capable of producing fever and ague, even when fiftered,. believing the miasmatic contagium to be soluble. But whether, or not, malariaidiseases may be propagated independently of vegetable organ isms, as vehicles, they are almost certainly propagated by scoh means as has been before remarked in this article, and in the article intermittent fever (q.v.). In badly severed quarters of a city, where typhoid fever and diphtheria prevail, the pabulum for the growth of vegetable organisms is furnished, often abundantly, and bacteria flourish and no doubt spread the poison of these diseases; but that they constitute, in themselves, the poison, is by no means dembustrated. Cryptogams flourish everywhere, but only in certain localities do they produce disease. We are almost forced to the conclusion that the real disease-poison, whether an organism or not, is independent of the other organ ism, the visible Adotking this hypothesis, we readily explain the non appearance of sonic diseases amongst us. For example, the Russian cattle plague has
never visited the United States. If it were produced by cryptogamic organisms, or any other organisms of appreciable dimensions without any contamination of associated virus, it would not be easy to conceive that it should not be generated here. So of the pleuro-pneumonia of cattle; this disease was unknown in this country till 1843, and the history of its importation is known. Is it to be supposed that the vegetable- organism which may be found associated with the disease did .not exist here previous to the intro duction of the disease? But the subject is an exceedingly difficult and complex one, and many circumstances may be used as arguments on either the question, which may, after all, require for its solution the application of the reasoning poweri as well as the processes of physical science.
The soil where armies had their camping grounds thousands of years ago, or where large cities flourished, may contain germs of disease' which have not , yet undergone decomposition; for. it is known that germs, as•in the seeds of 'plants, may retain their life for thousands of years under favorable circumstances. That human diseases have a human origin, as a rule, or in some instances an animal origin, i8 not at all improb able. The fact, for instance, that small-pox is produced by the contagion of a previous case of small-pox supports that view. It cannot be shown din/ small-pox was ever spor adic, and to believe that &gold or fungoid organisms must be present to generate it is• inadmissible, for vaccine lymph was so prepared by Chativeau as to be completely free from all organic cells, and still it retained the properties of a virus capable of transmit ting the disease. The fluid, however, was granular. Panum, with a view to test the nature,of septic pOisons, boiled putrid septic fluid:and, as lie claims, eliminated all the bacteria by repeated filtration, and yet the clear solution was capable of producing sep tieaunia. But it is quite possible that vegetable germs are often convenient carriers of disease, and it may be the only way in which seine diseases arc propagated, as, for instance, anthrax; and, moreover, it is possible that in this disease, and in some others, it is the vegetable germ itself which produces all the •pathological .conditions. The problem has not been solved. Some medicines, mineral as well as organic, are capable of producing certain specific pathological conditions without the aid of any organisms. Arsenic will produce, when taken internally, peculiar eruptions resembling urticaria, ptyriasis or psoriasis. Mercury will produce a peculiar condition called salivation, in which the germs assume a characteristic appearance, accompanied by other well known diseased conditions. It is also capable of producing an eruption on the skin like-that of eczema, and sometimes like that of measles. The internal administration of the common nettle is followed by a' peculiar vesicular eruption. Is it to be denied, in the light of such facts, that a septic poison, or any species of virus capable of producing specific pathological conditions, may be engendered in the blood without the introduc tion of organisms? That one disease may, with great probability, be generated by vege table disease gerins does not at all warrant the conclusion that other diseases are so produced, especially when it is observed that they are produced by contagion, and never sporadically. As to the probability of those diseases which are peculiarly epidemic being produced by vegetable organisms. unassociated with other disease-producing virus, it is doubtful if a positive opinion can be well founded. Indeed, the very facts which are brought forward to show that vegetable organisms are the generators of specific dis eases rather favor the contrary conclusion; as, for instance, the fact, before alluded to, that different species of algoid or fungoid organisms are capable of engendering inter mittent fever.
But what are disease germs? It cannot be doubted that the molecules of any com pound, even of the most simple, inorganic, are aggregations of atoms—for otherwise we cannot conceive of the nature of a compouud—an they must possess dimensions according to the complexity of the molecule. But when we come to consider complex organic molecules, we necessarily have in our minds bodies of much larger dimensions than simple, inorganic molecules, which latter probably contain only a comparatively small number of atoms. Whether it be possible for a microscope of the highest power, to reveal a.complex organic molecule like that of a proteid body, is, perhaps, a question_ difficult to settle. How near we come to the discovery in magnifying 5,000 diameters it is impossible to form an opinion. It is improbable that the powers of the microscope will ever penetrate into the molecular constitution of vital matter to that profound depth, in which the organic molecule is so elementary, as to be incapable. of a vitality of its own while surrounded by a proper pabulum; for if the instrument could ever be given sufficient power, it would probably reveal the fact that the smallest organic mole cule, even the ultimate, is a moving, living body, capable of growing and multiplying in its natural pabulum. It is therefore probable, that if such be the relation of to organic molecules, the continued increase of the power of the microscope would only reveal the existence of minuter and, still minuter bioplasmic bodies, previously invis ible. If disease germs can proceed from bodies which are invisible with the highest microscopic power, what organism is it which shall receive the designation of original disease germ? It may be that the ultimate molecule of living matter is as independently active as the aggregation of them which we call bioplast, and it may be asked how minute must be the bioplasmic particles, or the germinal particles, and, bow simple in constitution, before they lose their power of development andtmultiplication. Like the starry heavens, which only reveal more worlds with the increase of telescopic power, living, organic fluids seem to contain an almost infinite gradation of minute and more minute bodies. But wherever life begins and life ceases, there are boundaries between living and dead matter which seem impossible unless the particles are carried over by a power which is exclusively external, and which either confers vitality or destroys it. Is the organism which produces disease as a cell, an organic particle, or a simple poison without any organization consistent with vitality? Whatever it may be, the fact that it is capable of producing a repetition of pathological phenomena of a specific character compels us to regard as germ-like, and, therefore,-as practically a germ.