Imagens das páginas

digestion is for the metamorphosis of a sufficient quantity of the albuminous matters of the food. In the stomach of animals more of one element will be taken up at one time, and again, more of another

-a circumstance which, resting on experiments on artificial digestion, we might be inclined to attribute to a variation in the proportion of acid. This is, however, adjusted in the small intestines, by which arrangement but little of the substance is left unused.

On the Digestion of the Albuminous Matters of the Leguminosa. In reference to this subject, it is of importance to know how the natural properties of the matters in question are altered by the influence of a boiling heat, of acids, and of pepsin. Among the results of his experiments, the author states that the contents of the cells are molecularly altered by a boiling heat-perfectly coagulated if they have not become sufficiently diluted by previous solution in water, imperfectly if this has been the case. By treating pea-meal with water, we get, after separating the starch, a solution of legumin as it occurs in peas. This has always, even though freshly prepared, a weakly acid reaction. Authors are divided as to whether this fluid is or is not coagulated by rennet. Dr. Koopmans often added a neutral infusion of a calf's stomach to a fresh solution of legumin, and a firm coagulum always occurred after it had been for but a very short time exposed to a temperature of 100° Fahr., while no thickening took place in the same fluid under similar circumstances, but without gastric juice. By experiments upon a rabbit, Dr. Koopmans proved that a fresh infusion of peas is coagulated in the body also by acid gastric juice.

A solution of legumin in water is precipitated by dilute hydrochloric acid, and the precipitate is re-dissolved by the addition of more acid. On an average, the proportion of acid necessary to produce this result is . The acid in the stomach is, however, never so concentrated; immediate solution is, therefore, not to be expected; but by continued action a more dilute acid is capable of bringing about the same result.

On comparison with the solution of boiled albumen in artificial gastric juice, it appeared that the degree of acidity which digested this substance best dissolved the most legumin precipitated by a dilute acid from fresh infusion of peas, and that even after a very long time, just as with albumen, no complete solution ensued when the quantity of acid was too small.

Although legumin dissolves both in dilute acid alone and in gastric juice, the fluids thus obtained differ in their reactions, precisely as is the case with the other albuminous bodies soluble in acid alone. In the one instance peptons have formed, in the other they have not. The greatest difference between these two solutions consists, in the case of legumin also, in its being wholly or not at all precipitated on nentralization. This metamorphosis is of the highest importance for it also, in reference to its reception into the alkaline blood. If not changed into a pepton—that is, if not so modified as to remain dissolved when neutralized-legumin is unfitted for absorption.

In peas, legumin is coagulated by boiling. This is further almost always the case with its solution in water, but if the latter be made slightly alkaline, it will not coagulate completely on boiling, but will form a pellicle during evaporation. Towards gastric juice the coagulum does not, however, absolutely differ from coagulated animal albumen; by acids alone it is not dissolved, though it is by pepsin and a dilute acid; and this is best accomplished when the acid possesses the strength most suitable for the solution of albumen.

A principal essential condition for the digestibility of peas in the digestive apparatus of man, is the removal of the epidermis. If this be present, the digestive fluids cannot act at all on the contents of the cells; by long-continued boiling, however, the latter burst, like most cells; the starch swells up, and the legumin, partly coagulated, partly dissolved in water, is now rendered capable of metamorphosis. In some districts of the Danubian Principalities the inhabitants live exclusively on peas, and enjoy good health on this diet.

At all events, the fact is established, that for most men the seeds of the leguminosa, provided they are well prepared, afford an excellent article of food. Still more than for gluten therefore, in the relation of the legumin to the ordinary small amount of acid in the human stomach, must the solvent action of the fluids of the small intestine be taken into account, in order to explain the occurrence of a sufficient absorption.*

REVIEW III. 1. Small-pox and Vaccination. Copy of Letters from Dr. Edward

Seaton to Viscount Palmerston; with enclosed copy of a Report on the state of Small-pox and Vaccination in England and Wales and other Countries, and on compulsory Vaccination; with Tables and Appendices. Presented to the President and Council of the Epidemiological Society by the Small-pox and Vaccination Com

mittee. (Parliamentary Paper, 3rd May, 1853.) 2. On the Protective and Modifying Powers of Vaccination. By

EDWARD CATOR SEAton, M.D.-London, 1857. pp. 26. 3. Small-poxand Vaccination.” Articles in Copland's Dictionary

of Practical Medicine.' Parts XVI. and XVIII. 4. General Board of Health. Papers relating to the History and

Practice of Vaccination. Presented to both Houses of Parliament,

by command of Her Majesty.London, 1857. SINCE the Arabian physicians first described the ravages of small-pox at Mecca, the history of this once formidable and still loathsome disease may be considered in three great periods, each impressed with distinctive characters; and now the epoch of a fourth may be said to have commenced.

* [We regret to have to add to the analysis of the above memoir the announcement of the early death of its talented author, who, at the commencement of the present year (1857), at the age of twenty-three, fell a victim to typhus, taken in the active discharge of his duties as assistant-physician to the General Hospital of Utrecht.-Ed.)

The first of these periods is marked by an improvement in the treatment of small-pox, in which, more than in most diseases, medical opinion has undergone an obviously beneficial change. To Sydenham the merit of this change is due.

The second era is characterized by the discovery of a most singular custom practised in some countries, by which the severity of smallpox to the individual appears to have been greatly lessened. It was observed that the virulence of this poison was mitigated by introducing or engrafting the disease artificially into the system, through the cutaneous tissue. This was effected by propagating the disease from one person to another by the operation known as inoculation, in which the specific poison contained in the fluid of a mature small-pox vesicle was inserted into the skin of a healthy person. To Lady Mary Wortley Montague, as all the world kpows, is due the merit of having introduced such a practice into this country, in 1722; an achievement on her part, when measured by our knowledge in those days, which ranks with deeds of the greatest heroism.

"To the present time," however, as Simon writes, “it remains one of the most interesting and least explained facts in pathology, that the specific contagion or ferment of small-pox, so uncontrollable in its operations, when it enters a man in the ordinary way of his breathing an infected atmosphere, becomes for the most part disarmed of its virulence when it is artificially introduced to the system through a puncture of the skin ; so that a person exposed to this artificial infection very generally contracts the disease in its mildest and most tractable form.”

We need hardly here allude to the deficiency of information possessed on this point. We have in fact no accounts of the virulence of the effects of this poison if introduced artificially by punctures of the mucous membrane.* It may be that a less dose of poison is introduced artificially in either case than finds its way into the system when small-pox is contracted in the natural way.

The epoch which commences the third era in the history of smallpox is marked by a not less remarkable discovery, which has gained for the name of EDWARD JENNER an immortal and a well-merited fame. He discovered the protective power of vaccination, and how its influence modified the course of the disease which the poison of small-pox produced. In June, 1798, his great discovery was first communicated to the world in the form of a thin quarto of scarcely more than seventy pages; and dedicated to his friend, the late celebrated Dr. Parry of Bath. When still an obscure apprentice with a surgeon at Sodbury, near Bristol, he caught a glimpse of a great pathological truth, and became impressed with the conviction that a disease existed, communicated by contact from the cow, which was capable of protecting the affected individual from the occurrence of small-pox. Amongst the gossip of cowherds he had heard of a vague, obscure, but popular belief regarding the possible existence of such an occurrence, à belief wbich prevailed in the rural districts of Gloucestershire, and on the Continent in some distriets round Göttingen ; but it was by the life-long efforts of Jenner that this discovery was elaborated, and its importance to the welfare of the human race clearly demonstrated.

* The only experiment on mucous-membrane inoculation is that performed by Mead:

In 1721 (at the command of the Prince of Wales) he made the famous experiment of inoculating some condemned criminals for the small-pox. On six of the prisoners he tried the ordinary method, on the seventh, he carried out the Chinese plan, slightly modified-by introducing into the nostrils a pledget wetted with matter taken from a ripe pustule. This succeeded. All the criminals contracted small-pox, except one, who had had the disease previously. They all, too, recovered, and saved their lives ; going out of prison even safer than when they went in. The success attendant on this trial being thus eminently successful, the two young princesses, Amelia and Caroline, were inoculated on April 17th, 1722." ("Our Great Ones of the Past," Med. Times and Gazette, 1856.)

During the past few years, and especially since about 1830, a fourth era in the history of small-pox may be said to have commenced. A single definite characteristic can scarcely be assigned to the pathological belief entertained from that period till the present time regarding the relation of vaccination to the arrest of sinall-pox. The characteristics are different, according as we regard the progressive history of small-pox and vaccination in our own country, or in other countries of Europe.

The contrast which such an history presents in Great Britain and on the Continent does not show that in this instance ours has been "a highly-favoured land.” The comparison which some of the works at the head of this article have instituted on the protective and modifying influence of vaccination, as shown in the statistical records of this and other lands, is not honourable to our country-to its reputation as a nation, jealous and watchful of its national health, strength, enterprise, and wealth. Were we asked to give a character to this commencing era in the history of small-pox and vaccination, we should say that in this country the epoch is one of transition;" and that according as Government will organize and efficiently enforce those measures which Science has shown to be of the most powerful protective and sanative kind against the occurrence, the spread, and fatal character of smallpox, this transition will be for good or for evil.

A feeling of doubt and of scepticism has prevailed to some extent as regards the efficacy of the protective power of vaccination, with an ill-defined belief in some pernicious influence inherent in the practice of the operation, and with a tendency to propagate erroneous and absurd popular notions as to the nature of these supposed deleterious effects.

In some countries of continental Europe, on the other hand, especially in the central and northern parts, this epoch is now marked by implicit faith in the protective and modifying influence of vaccination, and by the consequent successful and efficient legal enforcement of the measure as a part of State Medicine.

Between twenty and thirty years ago (1820-1835) a combination of circumstances paved the way for the scepticism which unfortunately gained ground with some, not only in this country, but then also on

the continent of Europe; but it was not till during the past fifteen years that undercurrents of doubt found expression in no unmistakeable language, and which the renewed prevalence and spread of small-pox previous to 1840 tended to strengthen, or rather furnished an excuse for giving renewed expressions of opposition to the practice of vaccination, and misrepresentations as to the protection afforded by the measure. Besides the fact observed, and to a certain extent explained by Dr. Jenner himself, that all who were vaccinated were not completely protected, there were a host of theoretical objections propounded and urged with arguments of various force against vaccination. Physicians opposed the practice, and wrote pamphlets against it. It was written in those days that a bestial humour implanted in the human race would inevitably produce new and dreadful diseases ; horns would grow on the vaccinated, and a brutal fever would excite incongruous impressions on the human brain; these and such-like pyrological doctrines were dreamt of in their philosophy. Religion and morality no less gravely and absurdly denounced the “greatest physical good ever yet given by science to the world." Leviticus was quoted by learned divines, with dark insinuations against " contaminating the form of the Creator with the brute creation." And, to perpetuate the prejudice in another way, it is said that over the remains of Mr. John Birch, surgeon of the time to St. Thomas's Hospital, may still be seen, within one of the City churches in Rood Lane, a monument erected by his sister, which commemorates that “ The Practice of Cow-poxing, which first became general in his day, Undaunted by the overwhelming influence of power and prejudice, And the voice of Nations, He uniformly and until Death (1815) perseveringly opposed."

To the unipitiated the fight and the controversy was Doctor against Doctor ; and inquiries of an official kind were called for and successively instituted. The Royal Jennerian Institution made a solemn declaration, expressing their full belief in the incalculable benefit already derived from vaccination, and the advantage and security still in prospect from its use. The subject was discussed in Parliament, and by command of His Majesty the Royal College of Physicians of London were ordered to inquire into the virtues of vaccination. To carry out efficiently this royal command, they put themselves in communication with each of the licentiates of their college; they corresponded with the Colleges of Physicians of Dublin and Edinburgh, and with the Colleges of Surgeons of London, Edinburgh, and Dublin; they called upon the societies established for vaccination for an account of their practice; and they record their belief in the following remarkable paragraph, which closes their Report to the House of Commons in Parliament assembled in July, 1807:

“ The College of Physicians feel it their duty strongly to recommend the practice of vaccination. They have been led to this conclusion by no preconceived opinion, but by the most unbiassed judgment, formed from an irresistible weight of evidence which has been laid before them. For, when the number, the respectability, the disinterestedness, and the extensive experience

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