If common curtain rings are fastened to slides with shellac cement, colored with aniline blue, the joined edges of the brass film of which the ring is made being on the glass, and then subjected to a slowly increasing heat until the cement begins to burn, a very beautiful ornamentation is given to the under side of the ring, a circle of minute golden links making their appearance These rings can then be painted according to fancy on the turn-table and used for any kind of mounting.

I use this cement, colored with the various aniline dyes which are soluble in alcohol, for painting and finishing slides. These colors are far superior, for all purposes of ornamentation, to any other material or devices for painting; they dry quickly and adhere to glass with greater tenacity than any other cements that I have ever used.

For a cell that will perfectly withstand the action of Canada balsam or turpentine, I make use of the shellac cement colored with aniline blue, in the following manner: After a cell of the required depth is made on the slide and pretty thoroughly dried in the usual way, it is heated on the heating table, slightly at first in order to avoid bubbles, then gradually increasing the heat until the cement commences to smoke and the color to burn out. By heating one side of the ring a very little more than the other, as may be done over an alcohol lamp, a part may be left blue while the other is yellow or reddish, which has a very pretty effect under Canada balsam. These cells are hard as bone, and can scarcely be cut from the glass. Balsam has no effect whatever on them. Mountings on them may be finished off with liquid balsam, made true and circular with the point of a knife on the turn-table. In a few days, or in a shorter time by using the oven, they will be ready to clean and lay away. The cells which I have described are the only cement cells that can be used with Canada balsam. They are particularly adapted to vegetable stainings, algæ, and all other preparations either too thick or too tender to be mounted in balsam without something to sustain the thin glass covers.

In opaque mountings when cements of any kind are used, either for back-ground or to hold the object in place, I have found it highly advantageous to leave on, or in the lower part of the ring, a minute aperture opening into the cell, not necessarily larger than a cambric needle would make. With this provision both the cell and the cement go on drying, and there is no sinking in or moving about of the objects in the medium which holds them. If the cell be hermetically closed, one may expect that the object. will, sooner or later, be overwhelmed in a black sea. If curtain rings are used, a little notch can be filed in the side of them, and this be left open when the slide is finished.

If the opaque mountings are for dry objects, I make in the center of the ring a disk of Brunswick black or white zinc, accord

ing as the object to be shown is white or black. It may be of an inch in diameter for the Lieberkühn of the 1 inch objective, but not over inch for that of the objective. After the cement is dry and quite hard, a thin coat of balsam is spread over it and the objects placed in this and arranged if necessary under the microscope. The slide is then set aside to dry and may safely be covered the next day. If the object to be mounted will bear immersion in balsam, as some shells, seeds, minerals, etc., I pursue the following plan: The thin glass covers are cemented to some old slips, kept for the purpose, by two or three touches or the balsam applied to the edge of the cover, care being taken to center the cover on the slip by means of the self centering turntable. The objects are then arranged on a light coating of balsam on the center of the cover. When quite dry they should be completely covered by balsam and thoroughly hardened in the drying oven. Then Brunswick black or white zinc may be spread over the object, in thin layers at first, each being dried in the open air for a day before putting on the next, until an opaque covering is made for the object. Thoroughly clean the cover around the objects and then remove it from the slip by a slight heating. Then turn it over and mount it upon the cell prepared for it. Fasten the cover to the cell with gelatine softened by water to the consistency of jelly and then liquified by alcohol. Put the cover on the cell and apply the gelatine solution with a brush around the edge, leaving the little opening before referred to.. When dry the cell may be finished with liquid balsam, carefully avoiding the little aperture. The outer edge may be gathered up into a neat trim circle with the point of a knife on the turn-table. -C. C. Merriman, Rochester, New York. (Read at the National Microscopical Congress at Indianapolis, August, 1878.)

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SCIENTIFIC NEWS.

BRITISH ASSOCIATION FOR THE ADVANCEMENT OF Science. We conclude our account of the last meeting, which was, on the whole, one of the largest, most varied and pleasant that has been held for twenty years. Several of our American scientists read papers. Prof. T. Sterry Hunt made communications on the Metamorphic or Archæan rocks of America as compared with those of Great Britain, and also on the geological relations of the atmosphere. Prof E. D. Cope read papers on the Saurians of the Dakota formation of the Rocky mountains, and on the Vertebrata of the Permian formation of Texas. Mr. Graham Bell made a communication on the Telephone. Prof. Cook, State-geologist of New Jersey, was also present. of special interest, we note one in the zoological section by Sir Victor Brooke on the deer; a good point he made was the existence of a constant variation in the horn of Cervus dama, which

Of the papers

originated in an old buck, and now characterizes the entire herd in one park in West Ireland.

In physiology a good paper was the one on the location of sounds in the head on application of tuning-forks, telephone, microphones, etc.

In zoology another good paper was by Dr. Traquair on the structure of Ctenodus and Dipterus, in which he showed that the head of the latter is covered with segmented scuta like the sturgeon; the author brought out many other important points.

In general it may be remarked that the conduct of the meetings of the Association is very similar to that of our own. The tendency to complimentary criticism was probably rather more largely developed, but this did not prevent the fullest expression of adverse opinions when such were entertained.

As a good example of one of the evening lectures we quote, in part from the Dublin Irish Times, an abstract of Mr. J. G. Romanes' lecture on " Animal Intelligence," which attracted special interest; he said: "We thus see animal instincts may arise in either of two different ways, on the one hand, they may arise from the performance of actions which were originally intelligent, but which by frequent repetition have become automatic; and on the other hand, they may arise from survival of the fittest, preserving actions, which, although never intelligent, happen to have been of benefit to the animals which first chanced to perform them. But now let it be observed that although there is a great difference between these two kinds of instincts if regarded psychologically, there is no difference between them if regarded physiologically; for, regarded physiologically, both kinds of instincts are merely expressions of the fact that particular nerve-cells and fibres have been set apart to perform their reflexes automatically-that is, without being accompanied by intelligence. In making these observations we are not necessarily committing ourselves to the doctrine of materialism. That physiological phenomena are intimately connected with natural phenomena does not admit of doubt, but concerning the nature of this association scientific men declare not merely that it is at present unknown, but that, so far as they are at present able to discern it must forever remain unknowable. The restless tide of intellect for centuries has onward rolled, submerging in its arms those rugged shores whose name is mind, but at the lines where mind and matter meet there arises a mighty history like a frowning cliff, and in the darkness of the place we hear the voice of true philosophy proclaim: 'Hitherto shalt thou come, but no further, and here shall thy proud wave be stayed.' So much then for what I have called the physiological basis of mind. Passing on now to our review of comparative psychology, the first animals in which so far as I can ascertain we may be quite sure that reflex action is accompanied by ideation, are the insects. Well, remembering this distinction,

we shall find that the only difference between animal intelligence and human intelligence consists in this-that animal intelligence is unable to elaborate that class of abstract ideas the formation of which depends on the faculty of speech. In other words, animals are quite as able to form abstract ideas as we are, if under abstract ideas we include general ideas of qualities which are so far simple as not to require to be fixed in our thoughts by names." The lecturer also proceeded to show that animals had reason and judgment. "Passing on to the emotional life of animals, we find that this is very slightly, if at all, developed in the lower orders, but remarkably well developed in the higher; that is to say, the emotions are vivid and easily excited, although they are shallow and evanescent. They thus differ from those of most civilized men in being more readily aroused and more impetuous while they last, though leaving behind them but little trace of their Occurrence. As regards the particular emotions which occur among the higher animals, I can affirm from my own observations that all the following give unmistakable tokens of their presence: Fear, affection, passionateness, pugnacity, jealousy, sympathy, pride, reverence, emulation, shame, hate, curiosity, revenge, cruelty, emotion of the ludicrous and emotion of the beautiful. Now this list includes nearly all the human emotions, except those which refer to religion and to the perception of the sublime. These, of course, are necessarily absent in animals, because they depend upon ideas of too abstract a nature to be reached by the mind when unaided by the logic of signs. Time prevents me from here detailing any of my observations or experiments with regard to the emotional life of animals, so I will pass on at once to the faculty of conscience. In highly intelligent, highly sympathetic and tolerably well treated animals the germ of a moral sense becomes apparent. On the whole, therefore, I can only suppose that we have in these actions evidence of as high a development of the ethical faculty as is attainable by the logic of feelings when unassisted by the logic of signs; that is to say, a grade very nearly if not quite as high as that with which we meet in low savages, young children, many idiots and uneducated deaf mutes. In savages, as in animals, there was a remarkable tendency to act in accordance with performed habits rather than to strike out improved modes of action. Very young children present only those lower faculties of mind which in animals we call instincts. With advancing age, the first indication of true intelligence seems to consist in the power of forming special associations. On the general theory of evolution we should expect that in such a descending scale the characteristically human, or the more recently developed faculties should be the first to disappear, while those faculties which man shares with the lower animals should be the more persistent. And this expectation I have found to be fairly well realized. Beginning from

below, the first dawn of intelligence in the ascending scale of idiots, in the ascending scale of animals, is invariably to be found. in the power of associating simple concrete ideas. Thus there are very few idiots so destitute of intelligence that the appearance of food does not arouse in their minds the idea of eating; and, as we ascend in the scale idiotic, we find the principle of association progressively extending its influence, so that the mind is able, not only to establish a greater and greater number of special associations, but also to retain these associations with an ever increasing power of memory. In the case of the higher idiots, as in the case of higher animals, it is surprising in how considerable a degree the faculty of special association is developed notwithstanding the dwarfed condition of all the higher faculties. On the whole then, from the mental condition of uneducated deaf mutes, we learn the important lesson that in the absence of language the mind of man is almost on a level with the mind of a brute in respect of its power of forming abstract ideas.

The Association will meet next year at Sheffield, under the presidency of Prof. Allman.

-THE CONGRESS OF GEOLOGISTS AT PARIS. The existence of this body is due, firstly, to the exertions of a committee which met in Philadelphia during the Exposition of 1876; and secondly, to the energetic coöperation of the Geological Society of France, which took in charge the arrangement of the details of the organization. The officers selected by this body and elected by the Congress on its opening, were the following: president, M. Hébert; vice-presidents, England, M. Davidson; Belgium, DeKoninck; Canada, Sterry Hunt; Denmark, Johnstrupp; Spain, Villanova; United States, Hall; France, Daubrés and Gaudry; Hungary, Szabo; Italy, Capellini; Holland, Von Baumhauer; Portugal, Ribeiro; Roumania, Stephanescu; Russia, De Moeller; Sweden, Thorell; Switzerland, Favre; general secretary, Jannetaz; secretaries, M. Brocchi, Delaire, Sauvage and Vélain ; treasurer, M. Bioche.

The Congress assembled on Thursday, the 22d August, in the large hall above the commencement of the left wing of the Trocadero. To such of our readers as have not seen this building it may be interesting to remark, that it is situated on the side of a hill on the right side of the Seine, which slopes gently towards the bank of the river. It faces the main building of the Exposition which stands on the left bank, the two being connected by ornamental grounds, and by the bridge of Jèna. The building consists of a central portion of the form of a semicircle to which are added two long arm-like wings, which follow the direction of the circumference of a large circle for perhaps 120°. The convexity of the central building is inwards, and presents several porticoes, one above the other. From the summit of the lowest of these a wide sheet of water descends with a face con