M. PASTEUR INTERVIEWED.

New Zealand Herald, Volume XXV, Issue 8964, 31 January 1888, Page 6

M. PASTEUR INTERVIEWED.

HIS RABBIT SCHEME.

A TALK WITH THE GREAT SAVANT. The Paris correspondent of tho Sydney Morning Herald sought an interview with M. Pasteur on the publication of the latter letter in Lo Temps, explaining his scheme for the destruction of rabbits in Australia. I succeeded (writes tho correspondent) in obtaining one, although his door has been almost barricaded against visitors of late, in consequence of the very feeble state of his health and his urgent need of absolute rest. I found him in his simply-furnished suite of apartments at the Ecole Normale, and our conversation took place by the fireside of a small room, on one side of which was his bed and on the othor a table for writing and study. M. Pasteur looked pale and ill. He is suffering from congestion of the larynx, and he spoke in a feeble voice, with evident difficulty. I asked him, if JwtbelievEd Ihati the means he proposed, viz., the propagation of the epidemic known as foils' cholera would entirely remove the rabbit pest from Australia. He replied : — " I am absolutely convinced that- it .will, if the remedy is properly applied but it is ] one of those things it is very easy to do badly. One of the essential conditions of j success is that the microbes tfixjllj ( gated in a state of purity. Those! who havto made this branch of science their study in Australia— I have no doubt that there are persons there who have done sowill know exactly what I mean. Care must be taken to prevent other microbes which might destroy them or interfere with their development from being propagated with them. The microbes of fowls' cholera can be generated with amazing rapidity (in 15 or '2-1 hours), and in any quantity that may be considered desirable. The medium employed for this purpose should be some animal broth. This, together with the microbes, could bo easily preserved and distributed among the farmers who needed it,"

M. Pasteur went on to explain to mo that fowls' cholera was far more destructive to rabbits than to fowls ; that it spread with extraordinary rapidity, and speedily ended in death. In his opinion, the best means of propagating the disease was to sprinkle herbage placed at tho mouths of the burrows with the liquid. If a rabbit were to take the smallest quantity of it into its body, it would soon go back to its hole and die. There it would itself become a certain source of infection. Thus the epidemic would spread, and the animals would die in multitudes. Although this disease was so fatal to rabbits, it was absolutely innocuous with regard to cattle, sheep, and other farm animals. He had made it a special study in his laboratory. I pointed out to M. Pasteur that there might be some difficulty in obtaining the microbes in Australia, and suggested that, in order that the experiment might be tested without loss of time, it would be well to send a small quantity for propagation there. "If the Governor of New South Wales wishes me to do so," said M. Pasteur, "I will send him somo tubes containing microbes. I could in this way send a million in a small box. These tubes could afterwards be distributed among different persons in various localities, so that the propagation could be carried on immediately upon an extensive scale." He added that it might be well to delay tho experiment until the beginning of winter in Australia, because the microbe perished when the temperoturo rose above 50 or 51 degrees centigrade. He held that the practical application of his method was easy and inexpensive, but it needed care and scientific precision. The conversation turned upon the various means already taken in Australia and New Zealand to combat the rabbit pest, M. Pasteur said they were all inadequate. He looked amused when I told him that weasels and stoats had been imported to kill the rabbits. " Quite useless," he exclaimed, " a living poison is needed to destroy this prolific life. Modern science has taught us that it is the little beings that kill tho large ones (Ce .tout lex petit,i qui tucnt ha r/ros)." M. Pasteur also informed me that he intended shortly to adopt the method which he proposed for Australia and New Zealand upon a small scale himself, in France. A friend of his let loose a number of wild rabbits upon a portion of his estate, for the sake of the pastime of shooting them, but the animals had multiplied so prodigiously that they had become an intolerable nuisance. It was found impossible to keep them down by shooting or trapping. M. Pasteur, therefore, intended to spread among them, in the manner already explained, the epidemic of fowls' cholera. At present, however, he was not in a state to undertake anything of the kind. As I was leaving, he said to me: "If I were a younger man I would go out to Australia, and superintend the experiments upon the rabbits there."

In spite of physical suffering and weakness, which appeared at times to break the current of his thoughts, and render it difficult for him to talk, it was evident to mo that M. Pasteur took a keen interest in this rabbit question. Although the severe scientific discipline of his lifo must have made him extremely cautious of trusting even his own reasoning in the absence of positive proof to support it, his manner was that of a man absolutely confidontof certain results being obtained as the consequence of certain measures. He has no doubt whatever that his proposal, if carefully acted upon, will satisfactorily and speedily dispose of the rabbit plague, upon which so much money has been almost uselessly expended. In his letter to the Temps, M. Pasteur said :—" I am anxious that an effort should be made to carry death into the rabbit burrows of New South. Wales and New Zealand by endeavouring to communicate to the rabbits a disease capable of taking an epidemic form. Such a one exists under the name of fowls' cholera, and it has been the subject of very careful study in my , laboratory. This disease is equally applic-1 able to rabbits. Now, amttrtftHhe experi-] ments which I have conducted was the' following-.—l placed in a (limited space a; certain number of _ fowls,' and 'by -giving j them food contaminated by the microbe,.' which is the cause of fowls' cholera, they speedily died. Poultry yards are sometimes ravaged by veritable epidemics of this disease, the propagation,of which is, due, .without any doubt, to the defecations of the fowls originally affected falling upon the soil and the food. I imagine that the same thing would take place in the case of rabbits, and that returning to their burrows to die they would communicate the disease to others, which in their turn would propagate it. But how can wo make the rabbits in the first instance take into their bodies the destructive agent ? Nothing is easier. Around the burrow I would place a light fenco, enclosing a certain space where the rabbits seek their food. Experience has shown lis that it is easy to cultivate in a state of perfect purity, and upon a scale as large as may be desired, the microbes of fowls' cholera in broth obtained from some kind of meat. With this liquid, full of microbes, the rabbits' food should be sprinkled, and they would soon die here and there, and spread the disease on all sides. I have no doubt that in the infested countries there are persons quite ready to apply the method I propose method which is very simple, and is, at any rate, worth being tried." In this letter M. Pasteur uses much more guarded language than he did in his conversation with me. lie did not then say that he " imagined " that the rabbits would die like the fowls if the same means wore taken to communicate the disease to them ; he expressed himself quite positively, j on the subject.