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points upon which our knowledge of the sun and its surroundings has been advanced by this particular eclipse. It has been rendered tolerably certain that there is around the sun a selfluminous shell (the leucosphere), extending upon an average a sixth of his diameter beyond the hydrogen atmosphere, the principal constituent of which shell is that unascertained matter which gives the “1474” line; and that although this shell is self-luminous, it yet reflects some light from the brilliant strata beneath it. In the second place, it appears probable that there is a great extension, irregular in character and with a tendency to radiality, of matter which has either self-luminosity of the same kind as the leucosphere, though more feeble, or that has a special aptitude for reflecting leucospheric light. In the third place, it is pretty certain that there is a considerable scattering of all light not intercepted by the moon in and by some medium on this side of that body--either our atmosphere or a cosmical haze. This is as much as can be safely said upon the strength of the evidence now before us. More may possibly be inferred when a searching examination of the complete and detailed observations (which the Astronomer Royal has suggested should be made in connection with the undigested observations of the 1860 eclipse) is accomplished. It is much to be desired that this should be done before the time of the next eclipse—the 11th of the coming Decemberas it is not improbable that points of inquiry may be raised which that eclipse, from its peculiar circumstances, will afford special opportunities for deciding. The shadow will pass over the lofty Neilgherry Hills of India, and most valuable observations, bearing upon the question of the corona's atmospheric constituent, may be made at the exceptional elevations thus accessible.* The duration of totality there will be a few seconds over two minutes. In Northern Australia, however, where the shadow passes over Arnhem Land, the totality will last four minutes, and we hear with satisfaction that one observer, M. Bulard, of the Algiers observatory, intends to station himself there, most probably with photographic apparatus. And we may well rely upon the energy of the Australian astronomers to make the most of the occasion.

* Considering how the balloon has been pressed into scientific service, one cannot help wishing that a high balloon view of a total eclipse could be obtained; but there is no chance of an opportunity for such a view soon occurring.

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NYONE who would write the history of grafting might A readily fill a volume-a large one, and one as interesting as large. If he entered into technical details a great many volumes would be required. All that we have space to do here is to show that our forefathers were not ignorant of the practice, that the surgeons adopted it from the gardeners, that John Hunter made it the subject of experiment, and that in these days both surgeons and gardeners seem disposed to avail themselves yet more and more of the advantages it holds out. If we could induce any reader of a practical turn of mind, and a bent towards physiological enquiry, to turn his attention to the subject, we should be glad ; for although among gardeners especially great use is made of the grafting process, it is perfectly clear that a vast field remains yet for researchresearch, too, almost certain to yield profitable results alike to science and to practice. · Though so largely practised by nurserymen, it is really doubtful if we know much more about the matter than did the “ Scriptores Rei Rusticæ.” Columella knew how to bud roses ; he describes as many modes of grafting the vine as Beau Brummel had fashions for adjusting his necktie, while Virgil described the results with a neatness of expression that leaves only one regret—that the matter of his verse is less correct than the metre. It is the fashion to laugh at these old cultivators, who could wield the pen with as great facility as the pruning-hook, because their ideas of what could be done by means of grafting do not coincide with our own; but we should not be much surprised if in the future it turned out that the statements we have been accustomed to ridicule contain, nevertheless, much more of truth than is admitted at present. We do not venture to look forward to the time when apples shall grow on plane-trees, or ashen boughs enwreath themselves in a white mantle of pear-blossom,* or when hogs shall crunch acorns that have fallen from the overhanging elm. Possibly none of these things will come to pass, and yet others equally strange have happened, as we shall endeavour to show by and by, while much at least of what the old writers tell us is literally true. In hundreds of nurseries at this season pears are being grafted on quince stocks, apricots on plums, apples on crabs, so that Virgil's statement,

“ Nec longum tempus et ingens
Exiit ad cælum ramis felicibus arbos

Miraturque novas frondes et non sua poma," is as much a matter of fact as that if we commit a ripe seed to the ground under favourable conditions it will spring up in due season.

Who first among surgeons adopted the grafting process we do not know. Tagliacozzi (Latiné Taliacotius), who died in 1553, is the one most held in remembrance for his feats in requisitioning a portion of the skin of a bystander in order to supply the deficient organism of his patient. How this was done is told in language more expressive than polite by one Butler, and it may perhaps be said with justice that the “learned Taliacotius” owes his reputation among posterity more to the rhymes of Hudibras than to his own publications. John Hunter, who left very little unheeded as unworthy his attention, illustrated the grafting process by divers experiments, among which the most striking is perhaps the removal of the spur of a cock, and its successful implantation on to the comb. Hunter, too, practised a method of curing ulcers which has been revived within the last year or two by French surgeons, and carried out with much success in several of our own hospitals. The operation simply consists in the removal of minute pieces of healthy skin, and in their transfer to the diseased surface. Under fitting conditions, and with due precautions, adhesion takes place, the ulcer heals over, and what is usually a long and intractable sore is by these means rapidly and effectually cured.

We do not propose in this paper to enter at any further length into the historical or chirurgical portion of the subject. Our intention is simply to treat it from a physiological point of view, and to allude to certain facts or allegations which, if confirmed, will be of no small importance scientifically and practically.

* There is only a difference of one letter between the Greek words petia = ash, and undia=pear. Is it possible that Virgil, recalling what some Greek friends had told him, or what he had read in some Greek author, confused the ash and the pear? This is hardly likely, and would not account for the other anomalous cases of grafting ; nevertheless, the similarity is suggestive.

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