precipitated by alcohol and the salts of lead without impairing its activity.

Temperature has a remarkable influence upon the digestive power of pepsine; low temperatures suspend its action, while high temperatures destroy it altogether. It acts most vigorously at about the natural temperature of the body; above this point it becomes for a time more energetic, but finally reaches a point where it is entirely destroyed. The temperature of total destruction is supposed to be about 120° Fah. Certain substances also suspend its digestive power. Among these are alkalies, strong alcohol, and concentrated acids.

Bile completely and permanently destroys its activity. Pepsine differs from other organic substances in not being prone to putrefaction, and will even arrest the putrefactive changes going on in other substances.

The manner in which pepsine effects the solution of albumen is not definitely settled. It would seem not to be a purely chemical process, from the fact that the resulting albuminose or peptone, does not differ in chemical composition from albumen, and further from the fact that the pepsine still remains after the act of digestion has been completed, so that neither substance is destroyed, and no new body formed, as is the case in chemical combination.

Dr. BRINTON believes the change effected in albumen by the action of pepsine to be of the nature of hydration, i. e. that the albuminous solution is a hydrate of albumen, brought about by the action of the pepsine producing a chemical union of low grade, without altering the composition of either substance, and yet conferring new qualities.

Professor DALTON regards the process as one of catalysis; the contact of the pepsine with the food inducing a change of quality by a new molecular arrangement without alteration of composition. When an acidulated solution of pepsine has digested all the albumen it is capable of, or in other words is saturated, the resulting peptone or albuminose can be separated by dialysis and the same pepsine will again digest another equal amount of albumen, and this may be continued indefinitely. This is supposed to take place in the stomach, the organ acting as a dialysor, and setting free the pepsine to be reacidulated and to enter anew into combination with fresh portions of albumen.

The use of this subtance as a remedial agent preceded the physiological knowledge of its existence. Infusions of stomachs were in use in the time of GALEN, and the coagula

found in the stomachs of sucking animals were prescribed in the Pharmacopias of the 18th century. The lining membrane of the chicken's gizzard remained officinal up to 1746, and is even now extensively used as a domestic remedy for dyspepsia; but Dr. CokVISART was the first to develop the happy thought of aiding nature in her embarrassments by the use of her own agents. As a foundation for his clinical observations, he lays down the following rules or propositions:

1st. That aliment is an inanimate substance without nutritive power, per se, and without the aid of digestion it would not prevent starvation. Digestion alone gives it vital fitness and the capability of supporting life.

2d. The only thing necessary to produce this transformation of aliment into nutriment is acidified pepsine.

3d. That under the influence of this acidified pepsine, nitrogenous aliment undergoes the physical, chemical, and organic changes that they would under the influence of the gastric juice in the stomach itself.

4th. Artificial pepsine, aside from a different degree of force, is identical in effect with the gastric juice within the stomach, that is to say, its digestive power is always exerted in a similar manner. Further, if digestion by the aid of pepsine can be successfully carried on in an inert bottle or pouch, then so much the more in the living stomach which imparts in addition the natural motion and heat, although it may not itself secrete the digestive principle. The last general propo sition of CORVISART sums up the whole subject. He says if there is but one agent for producing digestion, under the influence of which aliment is made assimilable, and that by the aid of pepsine we can transform aliment into nutriment, we ought to be able by the use of the same agent to cause those to digest whose stomachs by a vice of secretion are deprived of this agent, this vital force which is indispensable.

In support of these propositions and conclusions, Dr. CORVISART cites a number of cases derived from the practice of distinguished confrères, all of them having well-marked symptoms of chronic dyspepsia, and all of them cured or very materially benefitted by the judicious use of pepsine and hygienic management.

Dr. HAWLEY related several well-marked cases illustrating the ordinary and well known effect of pepsine in common chronic dyspepsia due to impaired tone of the stomach, and consequently vitiated or diminished secretion of gastric fluid. Some are prone to cast contempt upon the use of pepsine as

a remedy, in consequence of the small quantity given in comparison with the large amount secreted by the stomach. Bearing in mind the physiological fact that a very small amount of pepsine may give digestive energy to a large amount of fluid, the force of this objection becomes very materially weakened. It is not only possible, but indeed highly probable, that the same pepsine may accomplish repeated digestions after successive absorptions of the resulting peptone by the gastric walls. Moreover it is not necessary to suppose that pepsine relieves indigestion only by as much as it digests food; we have reason to believe that it also exercises an indirect influence in restoring innervation, and thus, functional activity. That pepsine has an influence upon digestion, far beyond its simple power to digest, is made apparent by clinical observation. A single quotation coming from a source high enough to give it the weight of evidence upon this point, will suffice to prove this view of its action.

Dr. LEES, physician to the Meath Hospital, Dublin, says "where there is a disgust for food, you will find much benefit from pepsine, which generally causes an appetite." Had this been said of iron, quinine, or nux vomica, we should have regarded it as so much evidence of their tonic effect, and why not so in the case of pepsine? Another use for pepsine, and one which undoubtedly is followed by success, is in the vomiting of pregnancy. CORVISART early called attention to this fact, and cites a most remarkable case where the use of pepsine subdued the vomiting after the patient had been reduced to such a degree of emaciation that she resembled one in the last stage of pulmonary consumption.

Dr. GROSS relates six other cases followed by similar results, and believes the conclusion warranted, that pepsine exercises a controlling influence over the vomiting of preg nancy. In my own practice a case recently occurred favorably illustrating this part of my subject. Mrs. C., in the early stage of her first pregnancy, found herself unable to retain even the blandest articles of food. I prescribed ten grains of American pepsine three times a day. Visited her on the following day, and found that the vomiting had ceased after taking the first powder. And so far as I can learn, it has not since returned.

The next use of pepsine which I wish to call attention to is in the diarrhoea of infants. Premising that the great predisposing cause of infantile diarrhea is to be found in the state of evolution which the digestive system and its dependencies are undergoing during the period of dentition, the

question of therapeutics becomes one of comparative simplicity. The evident duty of the physician is to allay that irritation of the organs which exhibits itself in vomiting and purging, first, by the removal of all extraneous causes of disturbance, such as food improper in quantity or quality, and by protecting the skin from too sudden and frequent changes of temperature. Secondly, to subdue the excitement which the foregoing causes may have induced, which, in the enfeebled condition produced by the transition state, are more liable to persist; and, lastly, to impart to the struggling and overtaxed digestive apparatus that assistance which shall enable them to convert food from the character of a foreign body, and therefore an irritant material into nutriment which will sustain the natural forces, and enable them to accomplish successfully the great and necessary evolution through which they are passing. In this condition, owing to the want of balance in the system, there is constant danger that the ingesta may be converted into irritating substances, simply because there is not tone enough in the stomach to convert them into nutriment. Not only this, but the food, unable to sustain, may, in addition to acting as a foreign body, undergo putrefactive changes, and thus add another morbid cause to those already existing. In these cases the very function which is partially or totally suspended we can assist, and the very strength which is exhausted we can supply. By the administration of pepsine we reach at once the essence of the difficulty, by its aid we convert the ingesta into nutriment, and give the overtaxed stomach the first thing needful—rest.

Another valuable use to which pepsine may be applied is as an adjuvant to other remedies in the treatment of disease, especially in combination with cod-liver oil in cases of pulmonary tuberculosis and other developments of scrofulous or tuberculous diathesis. In these cases the oil is tolerated by the stomach, and there is less tendency to nausea. I have not, up to the present time, used it for this purpose, but have been informed by competent and careful observers, that much success has followed its administration in such cases.

The last use to which I will call attention is in the promotion of alimentation in disease. In a very able paper by Professor AUSTIN FLINT upon this subject, recently read before the County Society, we find the following sentence: "The limitations to alimentation in disease relate wholly to the physiological processes which are preliminary to nutrition, namely, digestion and the other processes by which aliment is converted into food." We infer, then, that to whatever

degree starvation may be a cause of death in disease, to whatever extent disease may overwhelm the powers of life in consequence of insufficient nutrition, to that degree and to that extent is artificial digestion important.

The only question remaining is whether artificial digestion can be successfully accomplished by the administration of pepsine. Undoubtedly it can. This is now a matter of recorded experience sufficiently extensive to remove all doubt. The Doctor here cited several cases from CORVISART and RILLIET, illustrating the successful use of pepsine in alimentation in typhoid fever.

Dr. HAWLEY, in conclusion, remarked that the therapeutical value of this remedy was not limited to the diseases already referred to. Its range is wider, and each practitioner bearing in mind the fact that it is more an aid to nature, than a remedy, will find various circumstances in the course of disease in which its use will be suggested, and especially where the treatment is restorative, there will pepsine at some point or other aid in the cure.

The article called American pepsine is a true representation of the gastric fluid obtained from the stomach of the calf, and prepared without the aid of heat. Its strength is uniform, and its merits are apparent from repeated experiments in which thus far it has proved superior in digestive power to any other preparation of the same kind. I do not, therefore, hesitate to recommend American pepsine as a reliable substitute for similar preparations of foreign production.

Change of Opinion.

SIR WILLIAM THOMPSON, in his late work on the urinary organs, expresses a decided preference for the flexible catheter over the inflexible silver instrument always used by Liston in stricture, and until lately, by himself. He writes on this wise: "I confess to a considerable change of opinion ever since I published my first work on this subject; and I do this without the slightest shame or the slightest repugnance. I hold that the end of life is not achieved in this world without change in our opinions. You may rely upon it, with regard to any subject whatever, whether politics or religion or our own proper profession, if we hold the same opinions at sixty as we do at forty, we live to very little purpose. It is an error to look for a life-long consistency' in matters of opinion from men who think for themselves, in whatever department their teaching may be. You must