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HOURLY MOVEMENT OF THE WIND (IN MILES), AS RECORDED BY ROBINSON'S ANEMOMETER.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8
10 11 12 13 14
15 16 17 18
Hourly 23 24 Means.
er or er er o
E con over vos
E ES CAN
1 10 4 18 6 14 7 3 10 2 13 4 6 8 6 6 15 11 8 4 12 7 9 8:0
1 20 2 16 4 15 6 1 15 3 16 4 5 9 5 7 15 12 8 3 12 7 9 8:3 5 0 14 1 13 8 12 4 1 10 2 15 1 4 9 6 5 18 10 15 13 8 10 7.6
1 15 10 9 7 16 1 1 9 11 11 2 5 9 6 7 17 11 10 3 13 4 9 1 16 2 7 11 18 1 1 6 1 10 1 5 11 5 9 18 12 4 14 8 10 707
5 11 16 1 1 7 1 12 1 7 11 7 8 18 8 10 3 15 10 10 7.7 1 96 | 8 12
1 11 21 11 1 4 7 7 19 9 10 3 13 15 & 7.6
8 1 1 9 3 10 13 8 11 22 9 13 5 14 16 14 10:1
4 13 18 19 12:0
3 14 19 18 12:2
The Anemometer was dismounted on the 25th, for the purpose of erecting a new instrument on the pattern decided upon for the Board of Trade observatories.
NOVEL ACTION OF LIGHT.
BY NIEPCE DE ST. VICTOR.
(Translated from "Comptes Rendus," No. 12, 1867).
I HAVE published, in five preceding memoirs all the experiments which I have made to prove that porous or rough bodies which have been acted upon by light preserve an activity capable of reducing salts of silver in the dark, as though they had been exposed to light. I have shown that this activity is persistent; that it is preserved for many days in obscurity or in the free air; that if a body had lost this activity, it could be made to resume it on exposing it again to light; that, supposing a piece of cardboard, was insolated, having been impregnated with nitrate of uranium, or tartaric acid, and shut up in a confined atmosphere, such as a tin case, hermetically sealed, it would have the same activity after several months as it showed on the first day.
This activity acts at a certain distance in the dark, for instance, and is communicated to a similar body in the same way, but the action does not pass through the glass.
M. Arnaudon, a chemist of Turin, has repeated some of my experiments in different gases, and the results have been the same as in free air. It would be very important to make an experiment in a luminous vacuum, but I have not as yet been able to do it. I proved the production of this activity upon the edges of a newly-broken china-plate, as well as upon an unpolished sheet of glass, made perfectly clean with distilled water. It could not be said, therefore, in this case, that there was decomposition of the body acted upon by light. I have shown that the effects of light are not owing to phosphorescence, but I have not said whence this activity comes. Many hypotheses have been put forward. Certain persons have denied the fact altogether, which was more simple; but no one has given a .solution to this phenomenon. I said, in my first memoir, that an engraving or a plain sheet of paper haying been insolated and afterwards placed on a layer made sensitive to light, such as iodide or chloride of silver, reduces salts of silver in obscurity, as though they had been exposed to light, only much more rapidly. If the sheet is impregnated with nitrate of uranium, or tartaric acid, before being exposed to the light, the reduction of the salts of silver is very quick, especially with the first substance.
This is, then, my experiment. I placed seven strips of red, orange, yellow, green, blue, indigo and violet glass
light» horescence, have been puth w
ned it.per while the blucot made any imprared, ora
upon a sheet of paper. After insolation, I have applied this sheet of paper to another sheet covered with iodide or chloride of silver, and have then left them in contact, in the dark, for twelve hours. I then saw that the bands of red, orange, yellow and green glass, had not made any impression on the sensitive paper, while the blue, indigo, and violet bands had darkened it. I repeated this experiment upon paper or cardboard impregnated with nitrate of uranium, or tartaric acid; the sensitive layer was much more coloured in the parts corresponding to the same rays than I have indicated above. When the sheet of paper containing nitrate of uranium, or tartaric acid, has been insolated, this activity can be easily proved by pouring a solution of nitrate of silver, in form of a train, upon the insolated part. A very strong colouring is immediately seen in the blue, indigo, and violet rays, and not any in the four first, except the exposition to light has been very much prolonged. In this case a slight colouring is seen in the green, yellow, and red rays, but not any in the orange. If bands of glass are placed on a sheet of gummed paper, and it is exposed for about an hour to solar light, on pouring a solution of iodide of potassium on the part covered with the seven bands of glass, the parts of the paper corresponding to the violet, indigo, and blue rays, would be observed to take a brick-red tint, while the green, yellow, orange, and red rays would remain unchanged.
If an iodide of silver is formed by pouring on nitrate of silver before the iodide of potassium, in the dark, the iodide of silver would be coloured in the most refrangible rays. By this means a sheet of paper can be insolated under a press, and a positive proof obtained in the dark, which can be strengthened by means of sulphate of iron. I ought also to mention, that I have made experiments with coloured glasses upon white and coloured stuffs, and the stuffs and the colours were only altered by the light under the violet, indigo, and blue glasses. I should say that light has less action under a violet than a white glass, and less under the latter than in open daylight.
Couclusions.—After these experiments, it can be said that light has only a destructive action in the most refrangible rays. That is known, it will be said ; but this persistent activity was not known before my experiments, and now I demonstrate that it is owing to chemical rays, and that it has the same effect as direct light in reducing salts of silver.
In our July number of the INTELLECTUAL OBSERVER, we gave an account of the discovery of what we believe to be the RONAN SIATION OF VINDOmis, in the neighbourhood of Andover ; and we bare to add that further discoveries have since been made near the same place. The Rev. E. Kell and Mr. C. Lockhart, to whom we owe these former discoveries, believed that other remains existed in connettion with them; and, on Monday, the 16th of September last, they were successful in their search. The fonndations of a second Roman building were discovered in the same Castle Field, at the distance of 250 feet to the westward of the one excavated in Vlas last. This new discovery is as yet of small extent; the four labourers employed uncovered the foundations of a wall three feet thick, composed of faced flints, for a distance of fifteen feet only; but there can be no doubt that it extended much further, and that, in fact, it forms part of some considerable building. What relation this may have to the building formerly excavated, it is impossible, with our yet imperfect knowledge, to conjecture. Among the antiquarian relics found in the course of the excavations were a Roman coin, third brass, of one of the Constantine family; numerous fragments of pottery ; pieces of stone roof-flags, which showed that it was the wall of a building which had had a roof; iron nails; some oyster-shells ; and bones and teeth of the ox, pig, etc. The farmer of the land, Mr. Turner, was unable to allow any complete examination of this new building to be made on the present occasion, as it was necessary to occupy the land immediately for agricultural purposes; but he has promised to allow the exploration to be continued in the autumn of 1868.
The Rev. Canon Greenwell is indefatigable in his researches among the YORKSHIRE BARROJTS. He has recently opened a group of seven, in the vicinity of Weaverthorpe, on the range of hills between Valton and Filey, two of which were very remarkable for the objects found in them. They were all of low elevation, from one to three feet; but this was perhaps the mere effect of time. The first of the two alluded to was two feet high by twenty-two in diameter. A skeleton, judged to be that of a female, lay on its left side, doubled up, in the centre, on the natural surface of the ground. On the right wrist was a beautiful bronze armlet, of the snake-head pattern, and a succession of oval swellings lengthwise. Close to the neck was a delicate bronze fibula, of the bow shape, extremely elegant in workmanship. It had originally a tongue of the same metal, which had been broken off, and replaced by an iron tongue. On the chest lay a necklace of extremely beautiful beads, fifty-two of glass and seventeen of amber. The glass beads, with one exception, were blue in colour, and ornamented with a zigzag pattern in white enamel; the exceptional bead being larger and more globular, and ornamented with amulets of white. Much broken pottery was found in the mound, with a few flint-chippings. The other barrow
was only one foot high by twenty-seven feet in diameter, and in the centre lay, on the surface of the ground, a female skeleton, also doubled up and laid on her left side. The right wrist, as in the former case, was encircled by a bronze armlet. It is described as being “ of the most beautiful description, resembling a delicatelyformed cog-wheel, with rounded teeth on both sides, the rim between the teeth being ornamented with three grooved lines. For exquisite preservation, delicacy and beauty of workmanship, high polish, and brilliant patina, this armlet is not to be surpassed." Below the hip were the remains of a plain urn “ of a peculiar darkcoloured ware.” A hole, or trench, in this tumulus, contained flint-chippings, animal bones, charcoal, and fragments of darkcoloured pottery. The rest of the barrows contained no very remarkable objects; in one only there were the fragments of a highly ornamented drinking-cup. We cannot quite see the evidence on which the writer of the local reports considers these barrows to belong to the late Celtic period, and why they are fixed at a date about one or two centuries before our era. We have given the description of the objects found in the two principal tumuli from the accounts published in the local papers, and it would be necessary to see them before forming any certain opinion; but, from the description, we should ourselves hardly judge them to be pre-Roman. In a cemetery at Seamer, in this same district, opened by Lord Londesborough in 1857, which was undoubtedly of the Anglo-Saxon period, probably of the fifth or sixth century after Christ, the body in one grave lay on its side, doubled up much as described above. An account of it has since been published in the “ Journal of the Archäological Association”; and we believe that, in the only other grave opened on that occasion, in which nothing but a skeleton was found, it lay in exactly the same position.
We have just received a new proof of the archæological activity and knowledge of Mr. Ecroyd Smith, in a pamphlet entitled, “ Archæology of the Mersey District," 1866, reprinted from the “ Transactions of the Historic Society of Lancashire and Cheshire," and containing much interesting matter. Perhaps the most interesting article in it is one which seems to fix the position of a ROMAN STATION which has been hitherto doubtful. It appears, from the second and tenth Iters of Antoninus, that a Roman road from Dera (Chester) entered the road which ran from Mancunium (Manchester) to l[ediolanum (supposed now to be Middlewich, in the centre of Cheshire), at a spot where there stood a town or station named CONDATE. Several localities have been put forward as the site of this place, but with not very satisfactory reasons. It has now, however, been discovered, by very recent diggings for sand, that numerous Roman antiquities are found at a place named Wilderspool, near Warrington, which answers to the Condate of the Itineraries in a very satisfactory manner; and, as we understand, appears, from other circumstances, to occupy the spot where the two roads met. The works, in the course of which the Roman antiquities are brought to light, are carried on in the present year with activity which promises important results. We owe this identifica