SCIENCE.

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The chief scientific event of the year, the total eclipse of the sun over a considerable extent of the South of Europe and North of Africa, naturally stimulated the exertions of the Astronomers and of other scientific men of all nations; and a threefold expedition was sent out by the British Government with the object of observing all its details as fully as possible. As the eclipse itself only took place on December 22nd, we have as yet no full accounts of what was the result. There is, however, too much reason to fear that few of the observers had the perfectly fine and clear weather they had hoped for, and, in Spain, as in London we know that the sky was much obscured by clouds, accompanied, around Cadiz, where the chief observations were to be made, with heavy and continuous rain. The following is a short report from Mr. S. J. Perry, one of the observers at San Antonio, near Cadiz :-Having prepared every thing by 9 a.m., 66 we were ready," he says, "to observe the commencement of the eclipse, should a break occur in the cloudy mass before us. Unfortunately, the break only came some forty-eight seconds after the first contact, when a distinct notch was observed on the solar disc. This break was only a change from thick cloud to thin cirrostratus, but we were enabled to observe the time of contact of the limbs of the moon, with several of the more remarkable lunar spots. . . . . . A very striking change of light on the landscape was noticed when little more than three-fourths of the solar disc was covered, and a chill was felt by all. . . . . . The moment of totality approached, and no chance remained of even a momentary break in the thin cirro-stratus that enveloped the sun and obscured most of the southern heavens. As the crescent became thinner, the cusps were observed first to be drawn out at length of several minutes, and then blunted; the well-known Bailybeads were formed, and the corona burst forth more than twenty seconds before totality. Viewed through a telescope of very moderate dimensions the spectacle was grand, but the clouds destroyed almost all the grandeur of the effect to the naked eye. The red prominences were numerous, but none apparently very remarkable. . . . . . The highest part of the corona appeared to the unassisted eye to be scarcely more than one-tenth of the sun's diameter, fading rapidly when one-fifth, but being still clearly visible at seven-eighths. Some observed two curved rays, but the general appearance was that of a diffuse light interrupted in four places distinctly, and, in a fifth, faintly, by dark intervals. The corona was white and rendered faint by the clouds. The darkness was never sufficient to prevent sketching with comfort without the aid of a lamp. Venus was alone visible. Totality ended by the formation of Baily's beads, and the corona was visible to the naked eye fifteen or sixteen seconds, after totality. The corona was seen for two minutes fifty seconds, totality lasting two minutes ten seconds. The clouds obscuring the sun appear to have almost destroyed all chance of detecting any except atmosphere polarization. Mr. Ladd remarked that the polarization was stronger on the corona than on either the moon's surface or the cloudy sky.

The view of the eclipse obtained near Arcos is described as very magnificent; a sketch was made there by Mr. Warrington Smyth. At the American Station at Xeres there was a break in the clouds which lasted somewhat more than half of totality. But Lord Lindsay's party was the most favoured in the country, having seen the sun through a rent in the clouds for five minutes, and this time embracing the whole of totality." In London, the

state of the atmosphere, with snow continually falling, was such as to preclude much hope of careful observations. Towards noon, however, the sky gradually cleared, patches of blue sky appeared, and it became no longer possible to view the sun without some protection to the eye. In a telescope of moderate power the sun presented an interesting appearance. His disc was reduced to a sickle of light, having its convexity upwards, and its two points nearly on a horizontal line-the breadth of the sickle resembled that of the moon when about four days old. Two large sun-spots, or rather a double group of spots connected by a relatively narrow zone of penumbra (or half-shadow), had come into view above and towards the right of the moon's disc. Numbers of minute and very dark spots could be seen around the two large ones and along the connecting streak of halfshadow. It is worthy of remark that this remarkable group of spots is the same which was observed by so many with the naked eye, when the sun appeared like a globe of red-hot iron during the fogs of last November. In October and September, also, the same wonderful group had been conspicuous; indeed, from the 23rd to the 26th of September, the sun exhibited so remarkable an aspect, owing to the presence of this great group, that scarcely a telescopist who observed it but was tempted to record its aspect pictorially. Until the end of the eclipse, which occurred about eighteen minutes to two, the sun, though occasionally clouded over, continued to be, for the most part, satisfactorily visible. The moon's edge, during the eclipse, presented here and there slight traces of irregularity, which, however, it was not always easy to feel certain about, owing to the condition of the air, and the ripples which continually disturbed the moon's outline. In the provinces the eclipse was seen, on the whole, satisfactorily, the weather being clearer, colder, and brighter, in proportion to the distance northwards, though, at the same time, a continually decreasing portion of the solar disc was covered by the moon. Total darkness extended over the zone in which are Cadiz, Gibraltar, Oran, Syracuse, and Catania, and hopes are entertained of the success of Mr. Lockyer's party of observers at the last-named place.

The meeting of the British Association was held this year at Liverpool under the Presidency of Professor Huxley, who delivered an address in the Philharmonic Hall, differing, and, we think, wisely differing, from many of the addresses given by his predecessors. It has been too much the character of previous addresses that their authors have attempted a thing in itself impossible, viz. the laying before the meeting a complete resumé of the science of the previous year. Professor Huxley, on the other hand, confined himself almost entirely to those branches of Physical Science with which he is best acquainted, and on which, therefore, he was entitled to speak as a master. His main subject was the working out, with great ability, of the one great Province of Biology.

Professor Huxley began by showing that the old and universal belief had been, practically, that of Lucretius, embodied as this is in the famous words of St. Paul -"Thou fool, that which thou sowest is not quickened unless it die;" in other words, the proposition "that life may and does proceed from that which has no life," was held by all the old philosophers, poets, and people of the most enlightened nations, and remained the accepted doctrine through the middle ages down to the seventeenth century. The first to attack the doctrine of spontaneous generation" was Francesco Redi, who, 202 years ago, came to the conclusion that maggots, for instance, are not generated by the meat, but by eggs, so to call them, brought through the air by blow-flies, and deposited on the meat. This was the commencement of the doctrine of Biogenesis, as opposed to

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the old view, which may be called Abiogenesis. "Omne vivum ex vivo" aphoristically sums up both Redi's doctrine and the limit he imposed on it. As years went on, the invention of the microscope, and its use in the hands of such observers as Leeuwenhoeck, Smammerdam, Vallisnieri, and Reaumur tended to confirm the general accuracy of Redi's views. In the middle of the eighteenth century, Buffon and Needham took up the question, and, with the aid of greatly improved microscopes, came to doubt the applicability of Redi's system to "infusorial animalcules," substituting for this the hypothesis of " organic molecules," as proposed by the former philosopher. According to this scheme, life is the indefeasible property of certain indestructible molecules of matter which exist in all living beings, cach individual living organism being formed by their temporary combination. This hypothesis is called from a word invented by M. Milne-Edwards, Xenogenesis, which means the generation of something foreign. But this hypothesis in its turn was overthrown by the acute experiments of the Abbé Spallanzani, who, indeed, showed successfully that Needham was wrong, though he did not prove that he himself was wholly in the right. The question was taken up again by Schutze and Schwann in 1836 and 1837; and, a little later, by Cagniard de la Tour and the illustrious Helmholtz, the latter of whom narrowed it to this-that if membrane, through which air could not pass, was placed tightly over the putrescible substance, putrefaction or fermentation would not ensue; and, therefore, that the cause of the development of the putrefying organisms must lie in something that cannot pass through the membrane. Finally, the researches of Schroeder, in 1859, cleared up the whole matter, by showing that air filtered through cotton wool neither putrefied nor fermented, nor developed living organisms-a view fully confirmed and supplemented by the remarkable experiments on air conducted during the last year by Professor Tyndall. Professor Tyndall, in fact, demonstrated that ordinary air is no better than a stir-about of exceedingly minute solid particles; that these particles are almost wholly destructible by heat; and that they can be strained off and rendered optically pure by being passed through cotton wool.

The next step was to prove that, among these solid, destructible particles there really do exist germs capable of giving rise to living forms; and this has been accomplished by M. Pasteur, who has shown, by aid of the microscope, (1) that the cotton wool, which had served as a strainer, does, as a matter of fact, contain these germs; (2) that these germs develope life on being sown in appropriate solutions; and (3) that the cotton-wool strainer can even be dispensed with, if the neck of the flask containing the solution be drawn out and bent downwards; for, under these conditions, if the solution within be properly boiled, no life will be generated in the fluid, even though the end of the neck be left open, for this simple reason, that the germs will not fall upwards, and that there are no currents to carry them into the interior of the flask. The evidence, therefore, in favour of Biogenesis, as opposed to Abiogenesis, is very strong.

Professor Huxley then went on to state that with reference to Redi's second problem, whether there is such a thing as Xenogenesis-that is, whether some living things are capable of producing offspring wholly different from themselvesthe researches of the last two centuries have led to a different result. The splendid patience of Van Siebold, Van Beneden, Leuchart, and others, have succeeded in tracing all such parasites, as the tape-worm, bladder-worm, fluke, &c., often through the strangest wanderings and metamorphoses, to an egg derived from a parent actually or potentially like itself. Thus a plant may throw off bulbs, but

these, sooner or later, give rise to seeds or spores which develope into the original form. A polype may give rise to Medusa, or a pluteus to an Echinoderm, but the Medusa and Echinoderm give rise to eggs which produce polypes or plutei; and they are, therefore, only stages in the cycle of life of the species.

The Professor then pointed out clearly the connexion between the diseases of the vine and potato, and the practical working of vaccination on the human frame. He then went on to give a very interesting account of the fatal disease under which the silkworm suffers, called muscadine, and of the researches which have been ultimately successful in arresting its progress. This disease is entirely due to the development of a fungus, Botrytis Bassiana, in the body of the caterpillar, and its contagiousness and infectiousness are accounted for in the same way as those of the fly-disease. Now the production of silk in France has of late years been so great that, in 1853, France produced one-tenth of the whole produce of the world, valued at about five millions sterling. If, therefore, the worms were largely destroyed, the loss would be enormous. Now, a short time before 1853, a peculiar epizootic, frequently accompanied with dark spots upon the skin (whence the name Pébrine), attacked the silkworms, the result of which was, that, in 1856, the silk crop was reduced to one-third of its previous yield; and, since then, till within the last year or two, it has never attained to half the produce of 1853. In 1858 the gravity of the situation caused the French Academy of Sciences to appoint Commissioners, of whom a distinguished natu ralist, M. de Quatrefages, was one, to inquire into the nature of the disease, and, if possible, to devise some means of staying the plague. The result was the discovery that the disease of which these worms died had, in its mode of occurrence and propagation, a remarkable resemblance, indeed identity, with that of the cholera. An Italian naturalist, Filippi, had found in the blood of silkworms affected with it a multitude of cylindrical corpuscles, each about 1-6000th part of an inch long; and it has been now clearly shown by M. Pasteur, that this devastating cholera-like Pébrine is the result of their growth and multiplication within the silkworm itself.

But M. Pasteur has done more than this. He has devised a method of extirpating the disease, which has proved to be completely successful whenever it has been properly carried out. "The direct loss to France," added Professor Huxley, in concluding his address, "caused by the Pébrine in seventeen years, cannot be estimated at less than fifty millions sterling; and, if we add to this what Redi's idea, in Pasteur's hands, has done for the wine-grower and the vinegar-maker, and try to capitalize its value, we shall find that it will go a long way towards repairing the money losses caused by the frightful and calamitous war of this autumn; and as to the equivalents of Redi's thought in life, how can we over-estimate the value of that knowledge of the nature of epidemic and epizootic diseases, and, consequently, of the means of checking or eradicating them, the dawn of which has assuredly commenced ?"

On the days subsequent to that on which Professor Huxley delivered his inaugural address, the meetings of the sections took place as usual, and at these a number of interesting and valuable papers were read, to which we shall briefly advert hereafter. It is necessary, however, first to notice an independent lecture, by Professor Tyndall, "On the Scientific Uses of the Imagination," which excited much attention at the time, as well from the abstruseness of its reasoning as from the bold, not to say dangerous, speculations put forward by him. Professor Tyndall is, we fear, an advanced disciple of Darwin, and has, as it would seem,

allowed his speculations to encourage in him the belief that the ultimate origin of life and mind, as well as of body, is material. That we may not misquote his views, we give his own words :-"The gist," says he, "of our present inquiry regarding the introduction of life is this-Does it belong to what we call matter, or is it an independent principle inserted into matter at some suitable epoch-say when the physical conditions become such as to permit of the development of life? . . . . . . . One question is this-Did creative energy pause until the nebulous matter (if indeed there ever was a period when this was the actual condition of our earth) had condensed-until the earth had been detached-until the solar fire had so far withdrawn from the earth's vicinity as to permit a crust to gather round the planet? . . . . . Having waited through these Eons, until the proper conditions had set in, did it send the fiat forth, Let Life be'? Now what is the core and essence of this hypothesis? Strip it naked, and you stand face to face with the notion that not alone the more ignoble forms of animalcular or animal life-not alone the nobler forms of the horse or the lion-not alone the exquisite and wonderful mechanism of the human body— but that of the human mind itself-emotion, will, intellect, and all their phenomena, were once latent in a fiery cloud. . . These evolution notions are absurd, monstrous, and fit only for the intellectual gibbets in relation to the ideas concerning matter which were drilled into us when young. Spirit and matter have ever been presented to us in the rudest contrast; the one as allnoble, the other as all-vile. But is this correct? . . .. Without this total revolution of the notions now prevalent, the evolution hypothesis must stand condemned; but in many profoundly thoughtful minds such a revolution has already occurred. They degrade neither member of the mysterious duality referred to, but they exalt one of them from its abasement, and repeal the divorce hitherto existing between both. In substance, if not in words, their position as regards spirit and matter is-What God hath joined together let no man put asunder."

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Many very excellent papers were read in the different sections, to some of which we shall here briefly allude; and to take first-Section A. Mathematical and Physical Science. Mr. S. A. Varley's paper, on "The Mode of Action of Lightning Coils," was very interesting. When storms occur in the neighbourhood of telegraph circuits, it is well known that powerful electric currents are often induced in the telegraph wires; in some cases, even strong enough to fuse the coils. But the interruption lightning causes on telegraph circuits is more impartial than the destruction it causes to the apparatus. To meet this evil, Mr. Varley constructed what he has called a lightning-bridge, consisting of two metallic-pointed conductors, approaching to within 1-18th of an inch, and surrounded by a mixture of conducting and non-conducting materials. This instrument has proved eminently successful, and there are now more than 1000 of them in daily operation in this country.

To Mr. Glaisher the meeting was indebted for a very able report on "Luminous Meteors for 1869-70;" to Mr. Main, "The Radcliff Observer" at Oxford, for an excellent paper on "Shooting Stars ;" and to Mr. Galton for a notice on "The Barometic Predictions of Weather"- -a paper full of his usual ingenious suggestions. Mr. Galton pointed out that the barometer corresponds, not with the tumultuous changes of the weather, but with those of its average quality, and that numerous trials had shown that the averages should be taken at about every twelve hours; it has been further observed that wind had far greater influence on

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