At a gathering like that of the British Association, which this year revisits Plymouth after a long absence, the value of the work done in the several sections is in truth quite independent of what may happen at the general meetings, which have a comparatively spectacular character, and whose object is to provide a sort of medium between the intimate scientific work of the Association and the diffused interest of the educated public. At the same time this object is an important one, and the remembrance of the proceedings left in the minds of outsiders in any given yearand consequently the amount of support beyond the pale of the properly scientific world which may be counted on to furnish the sinews of warmust depend in great measure on the impression made by the opening address. It is a thankless office to have to record, as we are now compelled to do, that this time the impression was not a very favourable one. In one word, the Presidents discourse was much too technical for the audience. It would be ungenerous to cast any person responsibility for this result on the eminent specialist who was chosen for the office. The gift of interpreting the results of highly special researches for the benefit of those who are not prepared beforehand for special knowledge is by no means a common onein fact, it is itself a specialty which very few have mastered; for which reason people who are anxious to parade themselves as amateurs in science are much in the habit of cheapening it. The notion that Professor Huxley and Professor Tyndall are mere popularizersbecause, forsooth, they can expound as well as discoverhas almost attained the rank of a vulgar error. Some remarks to that effect were heard at this very meeting in the Guildhall of Plymouth. Those who imagine that such remarks give them a scientific air may be assured that there is no more certain stamp of a narrow and superficial habit of mind. However, we cannot all go to Corinth; a specialist, however eminent, has not necessarily the gift of large and lucid exposition; and if he has not, the temptation to take refuge in the technical details of his own province is almost irresistible. Dr. Allen Thomson was himself aware of the danger, and made a most sort of apology by anticipation. He began with a general review of the history, position, and prospects of the Darwinian theory, which left nothing to be desired. This first part of the discussion, though not strikingly brilliant in form, was an excellent specimen of a kind of' scientific literature of which England has especial reason to be proud. It was quite fair, again, for the President being what he is, to lay special stress on the evidence of Darwinism in biology; and a passing notice of the current controversy on spontaneous generation was in every way fitting. Here Dr. Thomson declared himself in favour of those who hold that that no production of really new organic life has been shown to take place under the present conditionsin other words, he adopted the germ theory; at the same time be was careful to point out that the problem of the first origin of life on the earth remains quite open, and that no conjecture yet advanced does more than put back the difficulty. So far all was well; but presently the turn of the discourse became further specialized, and the audience found themselves listening to a severely technical lecture on embryology. Its main purport was clear enough, indeed, to those who knew in a general way what to expect. To others we think it must have been obscure. The Presidents speech was now of blastoderm, ectoderm, and endoderm, epiblast and hypoblast, and the less physiological part of the audience began to wonder if they had not strayed by mistake into the Biological section. Ignorance being the mother of fear, there were signs of alarm lest something improper should be coming; one or two very discreet parsons were observed to talk out. If they had stayed, they would  probably have carried away nothing worse than a more or less hazy notion that Häekel and Von Bär were very great men, and that the Amphioxus and Ascidians have become families of much greater consideration within late years. From indications we shall presently have to mention, it seems that Plymouth orthodoxy is still susceptible on the topic of Evolution; and it might perhaps have had a calming effect to assure the good citizens of all respectable denominations that the Amphioxus is a particular bête noire of those particularly naughty people the Positivists. We have not heard, however, that Professor Huxley has been in higher favour at the Vatican since Dr. Congreve put him under the ban of Humanity.
To return to Professor Allen Thomson, the general tenor of this more special part of the address was to set forth the parallel between the development of kinds, as conceived by tile Darwinian naturalist, and the embryonic development of the individual as it may be seen in any of the higher animals, from the microscopic ovum upwards through the various stages that lead to the finished form. On the evolution hypothesis, every such stage is the record of a condition once present in adult ancestors of remote generations; and this furnishes an explanationhow complete must be left for specialists to decide, but certainly the only explanations yet knownof phenomena in embryonic life which otherwise seem purposeless and unaccountable. Professor Allen Thomson has no doubt as to his own opinion; he pronounced the evidence of embryology in favour of the continuous development of species to be not only strong, but practically conclusive. It is impossible for an embryologist not to be an evolutionist; no theory which does not include the leading ideas of evolutionnamely, variability, adaptation, and hereditary transmissioncan bring the facts of embryology within a general law. The connexion and continuity of all organic life force themselves irresistibly upon the "faithful student," him who follows, according to Platos precept, whither-soever the reason of the thing leads him, not looking to the right hand or to the left.
Such were the general features of the address, which, valuable as was the matter, somewhat failed, as we have said, in immediate effect.. It was read with a tone of calm and equable familiarity proper for a discussion among expects, but hardly calculated to fix the attention of a mixed audience on the details of embryonic development. There was likewise another drawback, and one wholly beyond the Presidents control. The wise men of Plymouth seem to regard Darwinian doctrine as dangerously strong meat for their fellow-citizens, and the speeches that introduced and followed the discourse of the evening were apparently designed, instead of setting off and heightening its effect, to extenuate it as much as possible. The Mayor introduced Mr. Allen Thomson in a rambling oration (not unjustly received with bare civility) in which he took occasion to mention in an emphatic manner that, if the British Association studies the Book of Nature much, the men of Plymouth study the Book of Revelation more. It is true that Ply mouth is distinguished above other towns for the variety, vehemence, and eccentricity of its sectarians. It was reserved for the Mayor of Plymouth to discover that the temperament which has produced three rival sets of Plymouth Brethren is peculiarly favourable to the formation of sound judgment on scientific speculation. After this he launched into a display of classical allusions which Ajax and Prometheus got sadly mixed up. However, Dr. Allen Thomson was Prometheus, and if he did not meddle with fire nobody would peck him. The suggestion of a "winged hound of Zeus" in the back-ground who tears presumptuous men of science was not in the best taste. Then, after the address, the Earl of Mount Edgcumbe proposed the usual vote of thanks to the President, and said he thought the wisest course for the Association in such difficult matters as had been put before them was to "take the Presidents advice, and, instead of coming to rash conclusions, reserve their judgement so long as that branch of science remained in the region of hypothesis." This was a pretty bold piece of accommodation, considering that the President, so far from giving any advice of the kind, had said as distinctly as words could say it that in his opinion only one judgment was possible. Whether the Earl of Mount Edgcumbe really meant that he disagreed with Dr. Allen Thomson on his own ground, but did not like to say so, or whether he had any more subtle meaning, we shall presumably never know. Last came Mr. Acland to second the vote of thanks, and professed himself specially thankful to Dr. Allen Thomson for not having trespassed "in a light and useless way" on the forbidden ground of metaphysics. The terms of this compliment seemed intended to imply a censure on Professor Huxley and Professor Tyndall for their well-known Belfast addresses, and to suggest in a delicate way to the good folk of Plymouth how grateful they ought to be to the Association for not troubling with any such superfluity of naughtiness this year. Now it may be observed, simply from the Associations point of view, that the high problems of mind and matter at all events when handled by masters of exposition, are far more interesting than the development of epiblast and hypoblast, and much more likely to serve the objects for which it is chiefly worth while to have opening addresses at all. But this is also is to be observed, and is far more importantthat men of science need not and will not submit to purchase toleration by renouncing the right they have, no less than all other men, to discuss questions which lie at the foundations of science and are of the deepest interest for all thinking persons. As on the one hand they will not go out of their way to meet the so-called challenges of people who have not learnt tile elements of scientific method, so on the other hand they will from time to time pause in their special inquiries, when and where they think fit, to consider the bearing of established facts or probable hypotheses on the general conception of the world to be formed by a reasonable man. We believe that no doctrine about physical events, whether it be the conservation of energy, natural selection, molecular theory of gases, or anything else, can furnish proof or disproof of any metaphysical doctrine, though it may show in particular cases that something professing to be metaphysics is really bad physics. But it is perfectly idle to deny that the state of physical knowledge at any given time does materially affect the notions of mankind, both physical and metaphysical, about the order of nature as a whole. EIse why has science, as it has always had, determined enemies those who are or fancy themselves committed to keeping up particular sets of notions? The pretence of ignoring or deprecating these wider influences is unworthy of men who serve knowledge with a whole heart. Their business is to go straight onward, without fear and without favour, neither courting nor shrinking from speculative consequences, and least of all affecting to be, alone among all men, incompetent to discuss them.
C. Blinderman & D. Joyce