tissue was placed in a tube of glycerin broth and incubated for a fortnight. The broth and tissue are then placed into a shallow vessel and slowly desiccated. The dried mass was finally powdered in an agate mortar, a suspension made, and the bacilli counted by the usual manner of comparison with blood corpuscles, and killed by heating to 60° C. He believed that during the time of incubation the bacilli multiplied in the tissues.

Nicholls treated a case of leprosy, a patient of Sir Malcolm Morris, with this vaccine, which substance contained 50,000,000 organisms per cubic centimeter. He repeated this injection every 4 days at first, and later every 7 to 10 days. Under this treatment some nodules disappeared and others softened.

Rost (vide supra), in employing what he believed to be cultures of lepra bacilli, must have inoculated many lepra bacilli that had been carried over directly from his leprous tissue into the salt-free media he employed, and therefore his "leprolin," being a more or less concentrated suspension of lepra bacilli, may be considered as an example of a vaccine treatment for leprosy.

Whitmore and Clegg (118), 1910: After the latter had grown the bacillus of leprosy and isolated it in pure culture (Philippine Journal of Science, Vol. IV, pp. 77, 403), he and Whitmore prepared a vaccine as follows: A vaccine was made in the ordinary way and standardized to 500,000 bacteria per cubic centimeter. The bacteria in this vaccine showed a great tendency to form clumps on being allowed to stand without shaking.. Injections were given once a week, in doses varying from 0.25 to 1 c. c. of this substance. Any increase above this dose produced a local reaction, preventing the absorption of the bacilli, and later an abscess would form at the site of injection.

They treated 11 cases of leprosy in this manner for eight months and 21 cases for seven months. None of these cases showed any improvement, and the abscess production was a serious obstacle to this treatment.

They then employed a glycerin extract made in a similar manner to that prepared by Koch from the tubercle bacillus. They tested lepers with this material to see if they would give an analogous reaction to Von Piquet's skin reaction in tuberculosis, but their results were negative. They then used this glycerin extract in the treatment of the 32 cases of leprosy that had previously received the vaccine. No reaction followed this latter treatment, and there was no improvement. They then made a preparation by emulsifying their cultures of B. lepra in 1:60 aqueous solution of sodium oleate. The bacteria were almost completely dissolved by this fluid. They employed this soapy solution of the lepra bacilli on the previously mentioned patients. Under this last-mentioned treatment 2 of the patients had

a sharp febrile reaction, accompanied by swelling and redness around the leprous lesions. There was no local reaction at the site of injection, however. They continued this treatment for two and one-half months, but the patients showed no improvement under its use.

They then took the spleen of a leper (which organ was rich in lepra bacilli), ground up the tissue, added a 1:60 aqueous solution of sodium oleate, filtered it through cotton, and heated it for one hour at 60° C. This latter was given to the above-mentioned cases, but none of the patients so treated showed any improvement.

Williams (118a), 1911, by the use of ordinary broth and Rost's media, grew several organisms from cases of leprosy, no two of which organisms, however, appeared to be similar, varying from an acid-fast diphtheroid to a streptothrixlike form; and in one case an acid-fast bacillus. He considers it at least probable that the organism believed to have been grown by Rost, the streptothrix grown by Deycke, and the acid-fast bacillus grown by Clegg are the same as his organisms, and all of them pleomorphic forms of B. lepræ. His reasons for believing the above, however, are far from convincing.

From this organism, or more probably organisms, he has prepared a vaccine and used it on lepers, producing thereby febrile reactions, accompanied, apparently, by some improvement in some cases.

SPONTANEOUS CURES.

While all attempts to artificially immunize lepers against this disease have resulted in failure, nevertheless it is apparent that in exceptional cases the body itself is capable of establishing a sufficient degree of natural immunity in individuals once infected with leprosy to bring about what appears to be a spontaneous cure. The literature of leprosy contains many such examples; in fact, it is probable that every leprologist of any considerable experience could recall to mind cases of this kind. Some observers have gone so far as to state that it was doubtful whether a person ever had active leprosy more than 15 years, i. e., if he did not succumb to this disease by that time, that the active progress of the disease ceased, although, of course, the damages that had already occurred remain permanent.

Sufficient for the purpose of illustrating this point are the following references bearing on such spontaneous cures:

Cottle (119), 1889; Crespin (120), 1897; Montgomery-Douglas (121), 1903; Tonkin (122), 1905; Dubreuilh (123), 1905; Dyer (69), 1905; Hutchinson (124), 1905; and Kayser and van Houtom (125), 1905.

SUMMARY OF SOME OF THE KNOWLEDGE GAINED FROM THE ABOVE LITERATURE.

In studying the effects of the above-mentioned agents that have been used in the treatment of leprosy, it will be noted that most if

not all of them in the hands of certain observers and in certain cases have caused the patients to experience febrile reactions, followed by softening of old nodules, the reappearance of new nodules, etc. Such effects have often been considered as evidence that the substance administered was specific in its nature, and that the reaction that was obtained was analogous to that obtained in tuberculous patients when given tuberculin.

It appears to us, however, to be extremely doubtful that such conclusions are in the least justifiable, but rather that the mass of evidence we have up to the present indicates that anything that causes disturbances in the metabolism of a leper is often capable of bringing about the febrile and other disturbances mentioned. Similar febrile reactions are noted in lepers, accompanied often by disturbances in old lesions and the reappearance of new lesions, from many causes; not only from the hypodermic injection of the foreign substances, but from as unlike causes as exposure to cold, surgical operation, wounds and injury, pregnancy, etc., all of them causing more or less profound disturbances of metabolism.

For these reasons it seems to us that in treating leprosy and attempting to estimate the value of a remedy errors in judgment are especially liable to occur, and the irregular course of the disease itself further increases this difficulty of determining, after a short trial, the amount of benefit produced by a therapeutic agent.

While on the subject of literature we may mention that we have reviewed many articles bearing on the manufacture and use of various toxines, vaccines, etc., that have been employed in other diseases; but for the sake of brevity, and from the fact that the leading articles on these subjects are usually well known, we have not included these in our list of references. In our work of preparing the extracts of lepra bacilli we have especially followed the work of Koch in the preparation of his tuberculin and the other substances, and have in this connection reviewed, in the original, all of his articles bearing on his work along this line, from the time that he first announced his "old tuberculin" up to the preparation of his "bacillary emulsion." Most of our technique, in the preparation of these extracts, have therefore been but imitations of his work, with such modifications as the difference in the biological peculiarities of our bacilli and the tubercle bacilli seemed to make desirable. Thus, we started by using (like Koch did with the tubercle bacilli) suspended cultures of our organism, but we found, as Koch did with his organism, that such vaccines produced abscesses, or were at least slow of absorption. We then, like he, prepared a glycerin extract by growing our bacilli on glycerin bouillon, concentrating the latter down, and filtering it. Still later we ground our bacilli and centrifugated the mass, throwing down the unbroken, still acid-fast organisms to the bottom of the tube, and

saving the superimposed fluid, analogous to Koch's "T. O.," and by repetition of this process produced the analogue of "T. R." Of this we used very little, however, and next tried the complete grinding up of the bacilli (without separating "T. O." and "T. R." analogues) until no longer acid fast, followed by the collection of this structureless mass and its suspension in saline fluid; this latter corresponded to Koch's "bacillary emulsion," or, as is usually referred to, "B. E.” The use of live cultures and the use of the fatty extract was, of course, a departure from Koch's methods, but was not novel so far as the method is concerned, as live tubercle bacilli have been given to tubercular patients and Deycke has previously used the fatty extract of another acid-fast organism in the treatment of leprosy.

PRELIMINARY WORK.

Before the cultivation of the bacillus of leprosy by the method of Clegg had been effected at this laboratory one of us (D. H. C.) prepared two substances and employed them on lepers. Neither of these substances proved to be of value, but it is considered advisable to mention them here merely as records in the history of the attempts at specific therapy in this disease.

One of these substances was prepared as follows:

Six flasks were chosen, filled with 500 c. c. of glycerin bouillon and sterilized in the usual manner. One of these flasks was inoculated with B. smegma, another with one of the acid-fast grass bacilli of Moeller, another with the margarin bacillus, another with the urine. bacillus, one with the nasal bacillus of Karlinski, another with an acid-fast bacillus labeled "Lombard's pellagrine" bacillus. These 6 cultures of acid-fast bacilli were allowed to grow for a month at 37° C., when a heavy pellicle formed on the surface of the media. The cultures were then filtered, the pellicle collected and dried. The dried cultures of the 6 organisms were mixed together and ground in an agate mortar until the clumps had been entirely broken up. They were weighed and a 10 per cent suspension made in normal saline. solution. These organisms were killed at 70° C. for one hour, and 1 c. c. given intraperitoneally to each of 6 rabbits and 6 guinea pigs. These animals lost weight rapidly and died some six weeks after inoculation. The necropsy on these animals showed a white cheesy

1 Klemperer ("Experimenteller Beitrag zur Tuberkulose-Frage," Zeitschrift für klinische Medizin, vol. 56. 1905, p. 258) took tuberculous material from cattle (bacillus of bovine tuberculosis), and after passing this through guinea pigs, in hopes of lowering their virulence, administered these live organisms, taken from the guinea pigs, to persons suffering from pulmonary tuberculosis.

Webb, Williams, and Barber (Journal of Medical Research, vol. 20, 1909, p. 1) inoculated 5 tubercular patients with live tubercle bacilli, and these authors quote a verbal communication from Moeller that the latter investigator had inoculated tubercular patients with a culture of human bacilli after the organisms had been modified by passage through a crocodile,

mass in the peritoneal cavity at the site of inoculation. This mass was filled with acid-fast bacilli. As would be expected, the bacilli being dead, there had been no spread of the lesions beyond the site of the inoculation. It was therefore presumed that the animals died of a slow toxemia from the gradual breaking down and absorption of the bacillary bodies. Smaller doses (c. c.) were then given to other laboratory animals of the same species. They became greatly emaciated, but after several months' illness they all recovered.

After these preliminary experiments on animals this suspended, killed, mixed culture was given to 2 cases of nodular leprosy in doses of 1 to 2 minims by subcutaneous injection after diluting with normal saline solution. This treatment was continued over a period of nearly four months.

The injection of this material into the patients caused no local or general disturbances other than a slight redness at the site of injection, which, however, soon disappeared.

Two or three weeks after the beginning of treatment one of the patients had many of his nodules (which had not previously shown any tendency to soften) soften in the center and discharge, leaving round, punched-out, "craterlike" ulcers, surrounded by a rim of firm leprous tissue. At the beginning of treatment it was estimated that there were something over 300 small nodules present over this patient's body, varying in size from that of a pea to half an inch in diameter. At the end of three months' treatment about one-half of these nodules had broken down in the manner described. The patient's weight and general health remained unchanged throughout the treatment. Up to the time of discharge most of the ulcers mentioned remained unchanged, i. e., showed no tendency to granulate over, but a few of them had healed over. During the last two or three weeks this patient was under observation no further breaking down of the nodules occurred. For administrative reasons this patient, together with several others, had to be discharged at this time, so could not be treated any further.

The other patient that received this treatment began to experience the same breaking down of the nodules on their centers that the first-mentioned patient had shown, but in the case of the second patient, after 12 or 15 nodules had thus broken down into ulcers, the phenomenon ceased, and from that time up to the time of his discharge (four months from the beginning of the treatment) there were no changes in either his general condition or his lesions.

It was our intention to continue this form of treatment on other patients, but about this time the work which led to the isolation of B. lepra by Clegg's method changed our plans, and all of our energies were devoted to studying the effect of our newly acquired B. lepræ cultures and their products in the treatment of our patients.