proved by the fact that if the exhaustion of the tube be pushed to a yet higher degree, so that a practically perfect void be found containing neither air nor any other gaseous substance, the phenomena at once cease. But the odd thing about these "cathodie rays," as they are sometimes called, is that the rush of particles which they seem to indicate is so swift that if we suppose them to have any weight, the energy producing it must be sufficient, as Sir Oliver Lodge has lately said, to raise the British fleet to the top of Mont Blanc. Then came Dr. Röntgen and showed that this cathodie bombardment itself produced outside the tube the celebrated rays known as X or the unknown, which proved themselves capable of penetrating more or less perfectly all known substances, and therefore, though not themselves luminous, a photographic film; and which, unlike their parents the cathodie rays, were not drawn aside or "deflected" by a magnet placed transversely to them. Then came M. Becquerel, who showed that certain rare metals such as uranium and thorium, had the extraordinary property at ordinary temperatures of emitting rays which were in themselves streams of extremely finely divided matter, and which gave forth a feeble light when impinging on other substances. And all the time there had been under debate the theory alluded to more than once in this column, which is called the theory of "ions," and which teaches that when either a liquid or a gas is subjected to an electric discharge, its component atoms become split up into a number of yet smaller parts called "ions," each of them ridden by a charge of electricity and pressing forward some to the negative and some to the positive pole. Now all these phenomena seem to M. le Bon to be connected by one common feature, which is that they all tend

towards the discharge of an electrically charged body. Let a gold-leaf electroscope-to use the only instance he gives us-receive a sufficient charge to cause the gold leaves to diverge, and let the cathodie rays, the X rays, or the rays from one of M. Becquerel's light-giving metals fall upon it, and the leaves at once close as if they had been shot, thereby showing that the electric charge which before caused them to diverge is no longer there. But he has convinced himself that the same result attends every chemical reaction, such as, for instance, the mixing of a seidlitz powder, and that they are even produced spontaneously under certain conditions by all simple forms of matter. He therefore supposes that the "atoms" of chemistry which, as their name asserts, have hitherto been supposed to be indestructible and insolvable, are themselves composed of infinitely small particles of matter charged with neutral electricity, and in a variety of circumstances split themselves up into negative and positive ions, each of them bearing an enormous electric charge. This "ionic" electricity has also the power, according to him, when it meets any material obstacle of transforming itself into rays, which according to their different lengths may be, cathodie, X, or Becquerel rays, and which can pass through what we have been accustomed to call "solid" matter without losing their charge of electricity. These propositions he supports by experiments described at length in the "Revue Scientifique" of last month, and which are certainly well within the power of anyone with a very slender equipment of electrical knowledge and apparatus to repeat for himself. Into the truth or falsehood of M. le Bon's theory, I do not propose to enter here. It will doubtless be first accepted ad respondendum questioni-things having been of late too lively in electrical

matters for our pundits to assume towards any new discovery the air of contemptuous superiority sometimes displayed towards new ideas in other branches of science. It will then be fiercely questioned and probably as fiercely defended. Finally, if all goes right, it will take its place among the facts, according to the consecrated formula, definitely acquired by science, and everyone will according to their respective temperaments either declare that they had an inkling of it all along, or will else wonder why they did not think of it before. Thus do we arrive at truth, to quote again from one of M. le Bon's supporters, by successive approximations, and it is not for me to forecast the issue, although I may perhaps say that it seems to me a little unfortunate that M. le Bon should have put all his eggs in one basket, by confining, as he seems to have done in his published experiments, his inves tigations to the discharge of an electroscope only.

Whatever the issue, and it may well be that there are latent cracks in a theory which M. le Bon presents to us, after the manner of his clear and logical countrymen, whole, round, and polished, the consequences of the final The Academy.

acceptance of his theory are fairly enormous. The theories of vortexrings, and of waves in an ether whose existence is only hypothetically admitted, and has always been a puzzle to many of us, are at once swept away. It is doubtful, too, whether the official theory of the Hertzian waves-which M. le Bon hints may not really go through brick walls and large cantles of the earth, but only round them-or even the Clerk-Maxwell theory of light on which it is based, will survive. As for chemistry, the whole fabric will be demolished at a blow: and we shall have a tabula rasa on which we may write an entirely new system wherein matter will pass through matter, and "elements" will be shown to be only differing forms of the same substance. But even this will be as nothing compared with the results which will follow the bridging of the space between the material and the immaterial, which M. le Bon anticipates as the result of his discoveries, and which Sir William Crookes seems to have foreshadowed in his address to the Royal Society upon its late reception to the Prince of Wales. vivra, verra.

Qui

F. Legge.

The Life of Dr. Martineau, written with notable amplitude of detail, yet with becoming reserve, is before us in two portly volumes.1 The scope is large enough to satisfy the most exacting affection; the accuracy, even allowing for an occasional slip, is thorough and rare; the tone is reverent, the spirit independent, and the treatment throughout impartial while as fond as an admiring discipleship can make it. The first part is biographical, and cannot be charged with being either brief or frivolous; the second part, which is from another hand, deals with the philosophy, and is at once vigorous and lucid. The duplication of authorship has its advantages, for the field was at first so well gleaned that the second gleaner is tempted to carry off bodily some of the sheaves. Yet Dr. Martineau's significance is so much due to the philosophy he stood for that without a full study of him as a thinker his biography would not have been either satisfactory or complete. And the philosopher has here a lighter and more springy step than the biographer. The book, as a whole, may be said to be rather colorless, to want both the atmosphere and the background which were needed to bring out the propor

1 "The Life and Letters of James Martineau, by James Drummond, M. A., LL. D., Litt. D.

tions of the central figure. But its sobriety and its conscientious workmanship entitle it to a high place in the class of literature to which it belongs.

Dr. Martineau came of a fine stock, for in him the blood of the French Huguenot blended with the blood of the English Puritan. He owed to the one his keen and delicate intelligence, the elaborate elegance of his style and his love of the true as the Beautiful and the Good; and to the other his severe conscientiousness, his ideal of freedom, his ethical passion, his strenuous obedience to the conscience which he held to be the voice of God. It used to be said that Harriet Martineau was the man of the family and James the woman, but this biography proves the saying to be not even superficially true. There is in the man as he here appears a singular strength of will, integrity of nature and devotion to both intellectual and moral ideals. There is indeed a curious detachment in his friendships; though he is, in his way through life, anything but companionless, or unaccompanied by the affection that loves to admire and follow. But in his highest moods he dwells alone save for the God with whom he

and C. B. Upton, B. A., B. Sc. Two volumes, London (James Nisbet and Co.) 1902.

seems to speak face to face. Where he has a belief to vindicate or an ideal to pursue nothing personal is allowed to stand in the way. He has several beautiful friendships among the men of his own age, Charles Wicksteed, William Gaskell, John Hamilton Thom, John James Tayler; and these he loved with a devotion as rare at it was constant. And no one who ever heard him speak of the man to whose memory he dedicated his "Study of Religion," can ever forget the tenderness that stole into his austere face, flushed his pale features, and brought the tear into his introspective yet forward-looking eye at the mention of "the friendship" and "the companionship in duty and in study" which for thirty years made his lofty not a solitary way. He had many admirers among pupils, though perhaps but one pre-eminent friend. Richard Holt Hutton was not only a great editor, but also a clear if not a subtle thinker, a man of intensely religious and ethical nature who achieved much for the political education of his time because of the fine fusion in him of spiritual emotion with moral passion. Hutton was indeed an admiring disciple, but it is doubtful whether he ever fully appreciated what he owed to Martineau, to the solicitude that watched over his forming, and never ceased to regard wistfully the intelligence it had done so much to discipline. But Martineau's heart was given to ideas rather than to persons. This finds its best known, though not its most characteristic, illustration what we may term the affair of his sister Harriet. She must have been to use the very descriptive phrase which the elder Mrs. Carlyle applied to her own son:-"Gey ill to dae wi'," which means "not easy to get along with." But this temper of hers came from the same sort of moral integrity or ultra-conscientiousness which we have so frequent occasion to admire

in

in her brother James. A saying of hers was once reported to me by a friend who heard it, which shows the womanly instinct that guided her moral judgments. They had been talking of a distinguished philosopher and the affection he had entertained for his wife while she was still the wife of another. Harriet Martineau broke out in impassioned speech somewhat to this effect: "He had no right to indulge his affection at the expense of an innocent household. He had found a woman fairly contented with her lot, with a husband and a family living in comfortable good feeling each toward the other. When he realized that his affection for this woman was growing into a passion he ought to have withdrawn from her society and stamped out his feeling for her, but instead he continued within her spell and allowed it to become mutual and so potent that it alienated the wife from the husband, and broke up the family." And the man she thus severely censured she refused to count among her friends. The anecdote is repeated not to be endorsed, but simply to show that in Harriet Martineau there was a kind of moral intolerance which could not have been unknown to her brother. He had himself the same characteristic, though he had it under more masculine control. But the brother and sister were too much alike in their moral tendencies to get along easily together. Like a woman she was apt to defend opinions which were those of a person she admired, just as she was ready to despise the person who held opinions from which she strongly dissented. When she fell under the influence of Atkinson and their "Letters on the Laws of Man's Nature and Development" were published, her brother as one of the editors of the "Prospective Review" had to consider whether he should examine the book. He knew the temper of his sister, but he knew