powers. I simply wish to ask, has Dr. Carpenter described my test arrangements correctly, and were these arrangements scientifically devised and employed, or were they, as Dr. Carpenter maintains, absurd, and even childish? Dr. Carpenter says in the Nineteenth Century:

Nothing would have been easier than for Mr. Crookes, on the one hand, to have carefully watched Mr. Home, to have precisely imitated his whole procedure, and to have done his best to depress the board to the same degree by his own muscular effort; and, on the other hand, to have devised an 'indicator' for downward pressure by which it could be at once determined whether Mr. Home could depress the lever-board without such muscular effort. . . . The fact was simply that the lever-board went down when Mr. Home's hands were laid upon it; and the testimony of Mr. Crookes and his friends was quite sufficient to justify others in accepting it as such. On the other hand, Mr. Crookes's assertion that the lever-board went down in obedience to some other force than that of Mr. Home's muscular pressure was not a fact, but an inference drawn by Mr. Crookes; and this inference he had no scientific right to draw until he had assured himself by every conceivable test that Mr. Home did not and could not so depress it.

Dr. Carpenter also says that I have never published any proof obtained from these test experiments, although explicitly challenged to do so in the Quarterly Review, October, 1871.

Dr. Carpenter must surely know that the experiment to which he takes exception was merely the first of a series. Had he described the later experiments in full, the public could not have failed to perceive that the test which I am blamed for not trying would have been utterly useless. I will therefore briefly describe these experiments, which are given in detail and illustrated with woodcuts in the Quarterly Journal of Science for July and October, 1871. To meet the foreseen objection that while the attention of the observers was otherwise engaged, Mr. Home might possibly slide his fingers along the board and thus obtain leverage, I placed a vessel of water, with its centre exactly over the fulcrum of the board the extremity of which was attached to the weighing-machine. To prevent Mr. Home touching the bottom of the vessel, and to lessen the possibility of rhythmical agitation,' a copper basin with several perforations in its bottom was supported on a retort stand, so as to dip into the water in the first vessel. Into this basin Mr. Home plunged his fingers. By this arrangement it was rendered impossible for Mr. Home to obtain leverage-that is, if the doctrine still holds good that water transmits pressure equally in all directions. Further, the copper vessel acting as a breakwater, any rhythmical agitation set up by Mr. Home would be much enfeebled before reaching the bottom of the outer vessel. Yet, in spite of these precautions, the depressions of the board were substantially the same as when Mr. Home placed his fingers on the wood. But I went still further. I caused Mr. Home to place his hands not on the board at all, but on the table on which the fulcrum rested, first near the end of the board

and then at distances gradually increasing to three feet. Still the balance recorded great variations of pressure. Finally, while Mr. Home placed his hands in the position just mentioned, witnesses held both his hands and his feet. The result was still the same, the balance indicating ebbs and flows of pressure. I submit, therefore, that Dr. Carpenter's test would have been here a mere waste of time, and that I was fully justified in its omission. Indeed, it was as unnecessary as a determination of Mr. Home's 'downward pressure' on the chair on which he was sitting, or on his boots when standing.

One most significant conclusion which might be drawn, and which must surely suggest itself to every man of science who reads the history of the Radiometer, is the importance of residual phenomena. It is well known to chemists that of late years new elementary bodies, new interesting compounds, have often been discovered in residual products, in slags, flue-dusts, and waste of various kinds. In like manner if we carefully scrutinise the processes either of the laboratory or of nature, we may occasionally detect some slight anomaly, some excess or deficiency of action, some unanticipated phenomenon, which we cannot account for, and which, were received theories correct and sufficient, ought not to occur. Such residual phenomena are hints which may lead the man of disciplined mind and of finished manipulative skill to the discovery of new elements, of new laws, possibly even of new forces. Upon undrilled men these possibilities are simply thrown away. The untrained physicist or chemist fails to catch these suggestive glimpses. If they appear under his hands, he ignores them as the miners of old did the ores of cobalt and nickel. That in the experiments undertaken to determine the atomic weight of thallium I should at once detect a slight anomaly in the action of my very delicate balance, should consider it worthy of the most minute and protracted investigation, and should follow up the clue for so many years, is surely sufficient to refute the charge of imperfect training advanced by Dr. Carpenter at the close of his article in the Nineteenth Century. The moral might have been pointed with additional force by a reference to my discovery of thallium itself, which was likewise the result of the careful and systematic examination of a chemical residue, in which, when a mere boy, I had detected a chemical anomaly, and noted it for further investigation.

This great lesson-the importance of residual phenomena-must be pronounced of the highest moment to the student, and interesting, surely, even to the multitude. Yet Dr. Carpenter, addressing a highly cultivated class of readers, overlooks it altogether! He gives, indeed, an account of the origin of these researches,' and pronounces it rather singular,' but the moral he desires to point is of a totally different nature.

As I have said, Dr. Carpenter can draw but one lesson from the

analysis of my scientific researches, and he insists that it is criminal to be "possessed" of any ideas, or class of ideas, that the common sense of educated mankind pronounces to be irrational.' 14 But the 'common sense of educated mankind' at one time denied the circulation of the blood, and pronounced the earth to be the immovable centre of the universe. At the present day it upholds errors and absurdities innumerable, and 'common sense' has been well characterised as the name under which men deify their own ignorance. Are scientific men never to step over a rigid line, to refrain from investigation because it would clash with common-sense ideas? How far should we have advanced in knowledge if scientific men had never made known new discoveries, never published the results of their researches for fear of outraging this 'common sense of educated mankind'? Take the very subject which suggests the text for Dr. Carpenter's article. Can the wildest dreams of the spiritualist ask credence to anything more repugnant to common sense' than the hypotheses imagined by science, and now held to account for the movements of the Radiometer? In the glass bulb which has been exhausted to such a degree that common sense' would pronounce it to be quite empty, we must conceive there are innumerable smooth elastic spheres, the molecules of the residual gas, dashing about in apparent confusion, with sixty times the velocity of an express train, and hitting each other millions of times in a second. Will the C common sense of educated mankind' consider this rational doctrine? Again, both inside this empty space and outside it, between the reader and the paper before him, between the earth and the sun, occupying all the interplanetary space further than the eye can reach or indeed the mind can conceive, there is assumed to be a something indefinitely more elastic and immeasurably more solid than tempered steel, a medium in which suns and worlds move without resistance. Is not such a doctrine utterly incredible to the common sense of educated mankind'? Yet the kinetic theory of gases and the undulatory theory of light are accepted as true by nine-tenths of the scientific men of the present day; and doubtless in the processes of scientific evolution in the coming times many a discovery will be brought to light to give a sharp shock to the common sense of educated mankind.'

14 P. 256.

WILLIAM CROOKES.

MEDICAL WOMEN.

THE movement whose object has been to permit and to enable women to pursue the study of medicine, and upon passing the requisite examinations to become registered under the Medical Act, 1858, as legally or duly qualified medical practitioners,' dates, practically speaking, from the month of March 1869, when Miss Jex-Blake first made application to the University of Edinburgh to be allowed to attend the lectures of the Medical Faculty with a view to obtaining the degree of Doctor of Medicine, which would have carried with it the right to registration under the act. The readers of this Review may be safely presumed to be not unconscious of the broad facts of the struggle which has now ended in the accomplished fact of the admissibility of women to the ranks of the medical profession. The case is an instance, not uncommon in the history of movements destined to succeed, of an uphill struggle apparently against long odds, of doubtful progress, hopes disappointed or defeated, the patience and the courage of many trembling in the balance, and then at the moment of the greatest discouragement, the hour before the dawn, of a sudden collapse of opposition, and then of daylight and the haven reached. I hope that at such a moment it may not be entirely without interest to tell succinctly the tale of this endeavour, and to make clear the position which we have now gained..

To do this I must go back to the Medical Act of 1858. The purpose of that act, in the words of the preamble, was to enable 'persons requiring medical aid to distinguish qualified from unqualified practitioners.' The act provided for the constitution of a General Council of Medical Education and Registration of the United Kingdom.' The Council was to consist of representatives of the nineteen examining bodies of the country, and of persons nominated by the Crown. As a council of education it awaits the adoption of a scheme of conjoint examination by agreement or by law, to become practically operative; the registration clauses are in full working and of complete effect. The persons entitled to be registered, and none others, are the licentiates of any one of the nineteen examining bodies (s. 15); and by ss. 32, 34, 36, 37, and 40, no person can recover charges who is not registered under this act;

no person shall be held to be a legally or duly qualified medical practitioner' under any Act of Parliament unless he be also registered under this act; no unregistered person shall be entitled to hold any public medical or surgical appointment; no certificate requiring medical signature shall be valid unless the person signing be duly registered; and any person falsely pretending to be a registered person is made liable on summary conviction to a penalty of 201.

Clearly, as a consequence of these provisions, the practice of medicine in this country could only be open to women who should contrive to find their way on to the Medical Register instituted by the act; and this could only be accomplished by passing the examinations and obtaining the license of some one of the many examining bodies referred to. The following statement will show the difficulties encountered, and how they have been finally overcome.

The act recognises no foreign certificates or degrees, but it made an exception (Schedule A) in favour of persons already possessing the degree of M.D. from any foreign or colonial university, and already practising in this country before the 1st of October, 1858; and one English lady, Dr. Elizabeth Blackwell, having obtained a degree in medicine, in 1849, from a college in the State of New York, took advantage of this exception, and obtained registration in this country.

In the year 1860 Miss Garrett (now Mrs. Garrett Anderson, M.D.) began the study of medicine in England with a view to registration and practice under the Medical Act. After trying in vain elsewhere she was accepted as a student at Apothecaries' Hall; she attended some classes in common with male students; in lieu of attendance upon others, which was not permitted, she was compelled to pay comparatively heavy fees for separate and private tuition by recognised teachers. She had difficulties in obtaining hospital instruction, which in her case, however, were in time surmounted, and in 1865 she was registered as a licentiate of Apothecaries' Hall. Her title of M.D. she owes to no English examining body, but to a foreign university. The marked distinction with which she passed her examination in Paris is well known, and her equal distinction and success in the practice of her profession are matters both of general and professional recognition.

I have not dated the movement from Mrs. Garrett Anderson's personally successful attempt, because its immediate consequence was the closing of the door through which she had forced her way; the Apothecaries' Hall signalising the fact of her admission by the passing of a new rule, which forbade students thenceforth to receive any part of their education privately, whilst it was known that from some at least of the public classes women would certainly be excluded.. Her honourable place appears to me to be that of a forerunner of the movement, which she has, however, continuously aided, and now aids, VOL. I.-No. 5.

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