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508 LOOTOBER 23, 168 THE PHOTOGRAPHIC NEWS. exposed, and we have little more than very dense marks showing the protuberances. The six plates arranged for were duly exposed, but the heat so concentrated the nitrate of silver solution, that, besides showing but faint traces of any corona, they are all covered with spots. Still we may make something of them, and will try. Our first impulse, on reading such a statement as this as the result of such an expedition on such an occasion, was to repeat the famous sentence of Ruskin, “ This is not failure, but disaster!” Compared with the results obtained by Mr. Warren de la Rue in Spain, in 1860 ; compared with those secured by the German expedition, and recorded in our pages by Dr. Vogel, such an issue as the above is most humiliating. The plates were under-exposed, and covered with spots, we are told, as though the possibility of guard ing against such contingencies was a thing undreamt of. In a subsequent letter to Mr. Warren do la Rue, Major Ten nant is more hopeful, and better satisfied with the results obtained. The extract from his letter, published in the Athenceum, is as follows :— ' I did myself the pleasure of sending Mr. Airy a report, such as I could hurriedly make, upon the 18th, of what we had seen and done. Since then wo have been enlarging the photographs, and I am very well satisfied. The clouds reduced the actini sm very much and very unequally, but that has shown new things to me. 1st, there is very little corona; 2nd, the cloudy structure of pro minences is very marked. But the most remarkable thing is a great horn, which seems to have been 3m. 20s. nearly high. I have, as I told Mr. Airy, clearly seen in its spectrum C D and b, and believe I saw F, but did not identify it. Now this shows, both in Nos. 1 and 3 [photographs], as a ribbon of light, coiled spirally round a semi-transparent centre. It is very beautiful, and marked in 3, which was taken two minutes after the [commencement of] totality, and I am doing my best to keep this feature [to retain this feature] in the copies. No. 1 was taken apparently before the last of the sun went. Phillips [one of his assistants] says it was, and there is a spot of fog such as would be the result. There is a fine line of light seen through all this fog, much brighter than the corona. This, too, I am keeping on enlarging. We have got six enlarged positives, about 2} inches in diameter, from each nega tive. Every one of these shows the same remarkable spiral struc ture in the great horn. I find there are traces in a drawing which Dr. Janssen got made of that prominence [mentioned in the first part of his letters as invisible to the eye] of which I spoke. The positive copies I will enlarge to 9 inches. The result of the under-exposure, it is here suggested, was less injurious than was at first suspected ; but the multitude of spots, from the nitrate of silver becoming “concentrated,” of course nothing can remove, and their presence must seriously interfere with the value of the photographic record of the eclipse. A Fellow of the Royal Astronomical Society, writing to us on the subject, has some excellent remarks, from which we make one or two extracts. After calling our attention to “ the igno minious failure of the photographic part of the expedi tion,” he adds, that it seems to have occurred “ simply because, to the best of my knowledge, there was not an ex perienced photographer among the expedition who knew how to prevent the nitrate of silver solution becoming so concentrated that it produced a mass of spots. It is true, a certain number of the party had been taught the opera tions of photography at Crauford Observatory (i. e., W. De la Rue’s) shortly before starting; but was that sufficient to insure success ? Why not have procured the services of an experienced photographer, such as accompanied the expedi tion to Spain, in the person of Mr. Downs (of the firm of Cundal and Downs) an ‘ old hand ’ at all the ins and outs •of photography ? Or, perhaps, better still, the expedition might have procured the services of an Indian photographer who knew how to arrest the rapid concentration of nitrate •of silver ! “ The German Expedition, as per your insertion of Dr. Vogel’s letter, have secured three perfect negatives without ■spots. And why? Because the party composing that expedi tion numbered at least three thoroughly experienced photo graphers ampng them, clearly showing that they, at least, knew what was wanted to insure success as regards the photographic part of the expedition. ‛ What excuse has the Royal Society for this signal failure ? for every practical photographer who has read Dr. Vogel’s letter, and who now reads Major Tennant’s, cannot fail to divine the cause of non-success of the English Expedition.” This expedition was sent out by the Royal Society, aided by Government, and we fear very much that it is to the aid of the latter much of the failure may be attributed. It is probable, in fact, that it is due to red tape. A staff of men provided by Government might or might not be fitted in all respects for the work ; but if the men “ told off ” for the duty knew nothing of photography, it would be against all precedent to import a photographer from another department. If the men were selected from the Engineers, and they were not familiar with photographic operations, it would be quite inadmissible to introduce amongst them men from (say) the Artillery, who were skilled photographers. It is probable, from what we can learn, that to a cause of this kind the failure in result was due. Be this as it may, however, it appears tolerably clear that no experienced photographer formed part of the expedition staff, or we should not have heard of such puerile difficulties as spots from concentration of the silver solution. The photographic operations of the German expedition, so well described in our columns, were admirable in their systematic prevision. Possible forms of failure were antici pated and carefully provided against. The condition of the various chemicals was carefully tested, and the relative work ing conditions of various collodions ascertained under the precise circumstances in which they would be required. Preliminary exposures were tried on the spot. In short, everything was so well rehearsed, and every one so carefully told off to his duty, that failure from preventible causes was scarcely possible. If this expedition were distinguished by anything of military routine, it was in the efficient drill by which they prepared themselves for actual operations ; whilst the one military element which was missing in the expedi tion in India was this effective drill. We have in this country several photographers of high repute and great practical skill who have had experience in Eastern photography, and who have succeeded amid the gravest difficulties. Wc refer to such men as Bedford, and Frith, and Goode. Surely it would have been possible to have secured the services of some of these or other experi enced photographers, to whom the purely photographic ope rations should have been confided, and who would have certainly secured immunity from the disasters attending con centrated silver solutions, and probably, also, from the risk of under-exposure. We add here the remaining paragraphs of Major Tennant’s letter to the Astronomer-Royal:— Capt. Branfill reports the protuberances unpolarized, and the corona strongly polarized everywhere in a plane passing through the centre of the sun. Complementarily, I have to report a continuous spectrum from the corona, and one of bright lines from the prominence I examined. I am, I believe, safe in saying that three of the lines in the spec trum of the protuberances correspond to C, D, and b. 1 saw a line in the green near F, but I had lost so much time in finding the protuberance (owing to the finder having changed its adjustment since last night) that I lost it in the sunlight before measuring it, and I believe I saw traces of a line in the blue near G, but to seo them clearly involves a very large change in the focus of the tele scope, which was out of the question then. I conclude that my result is, that the atmosphere of the sun is mainly of non-luminous (or faintly luminous) gas at a short dis tance from the limb of the sun. It may have had faintly luminous lines, but I had to open the jaws a good deal to get what I could see at first, and, consequently, the lines would be diffused some what; still, I think I should have seen them. The prominence I examined was a very high narrow one, almost to my eye like a bit of the sun through a chink in brightness and colour (I could see no tinge of colour), and somewhat zigzagged, like a flash of light ning. It must have been three minutes high, for it was on the preceding side of the sun near the vertex, and was a marked ob ject, both in the last photo plate just before the sun reappeared, and to the eye. Captain Branfill saw the prominences coloured, as did two other gentlemen; but one in my observatory (like myself) only saw it