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Having thus brought to a conclusion an attempt to condense into a brief abstract the most useful parts of M. Ramond's Instructions, I propose, in a future communication, to subjoin an outline of the demonstration of the formula; together with a few remarks on one or two other points connected with the subject. B. P.

(To be continued.)

ARTICLE VII.

Notice upon the Volcanic Island of Milo. By Sir Francis S. Darwin, MD. &c. (With Plate XXII.)

SIR,

(To the Editor of the Annals of Philosophy.)

Buxton, Aug. 20, 1823. OBSERVING your analysis of the water from what you call the boiling spring of Milo, in the July number, 1819, of the Annals of Philosophy, I presume that the following description of that island, taken from my manuscript journal, may be interesting; I beg to offer it, and shall be happy if it affords any information to your readers.

I remain, Sir, your obedient humble servant,
FRANCIS S. DARWIN.

* O. S. xiv. 27: see also p. 68 of the present volume.

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SMALL BASALTIC ISLANDS NEAR MILO.

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Engraved for the Annals of Philosophy for Baldwin. Cradock & Joy Oct. 11823.

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In the month of June, 1810, we landed at Milo, and proceeded to the Old Town, which is quite ruinous, although a few inhabitants still occupy some of the houses. The ancient walls bear the marks of great waste and decay. Four miles from this is the New Town, situated upon one of the most elevated parts of the island. The incursions of the Algerines, and the plague, induced these few hundred people to neglect their former low situation (the old city) for this elevated one. On the foot, and at the side next the sea, of the hill upon which the present town stands, are many very interesting remains of a most remote period. We could distinctly trace the extent of a large amphitheatre, and many beautiful marble columns are seen amongst the ruins. Walls of immense thickness;-and the cement by which these stones are held together, appears to brave the waste of time better than the hard stone itself. The highest point of Milo, or Mount St. Elias, is about 800 feet above the sea, and it is of a conical shape; this summit was formerly a place of observation for pilots, but now for pirates, who infest the Archipelago. On the north side of the island, and half a mile from it, are some curious basaltic rocks, which do not appear to contain zeolite; but there are no columns on Milo itself. Upon ascending from the harbour to the town, we pass over hills and rocks of lava, in which opal is found, with pumice stone, and sulphur, and beds of limestone which have been burnt, and still retain many perfect shells, which soon absorb moisture, and fall to pieces in the hand. In one part of a rock of red sandstone, at about the middle of the entrance into the port, are some singular Catacombs in the perpendicular rock, some of them capable of containing four, six, or eight bodies, and they are seen in the side of the cliff ten or twenty feet below the level of the water. This is a strong proof that the harbour was the crater of a volcano, as here there is no tide, and these tombs must have been formed before the grand eruption which gave access to the sea. The situation of these sepulchres is marked upon the chart. It occurred to me on seeing in the map (which was partly copied from an Admiralty book), that 40 fathoms was the greatest depth in this large basin, that there might be a part infinitely deeper which had been the real furnace of the volcano. I was at great pains in sounding, but could no where find it to be deeper, except at the entrance. On the west and south sides of the harbour are innumerable hot sulphureous springs, some of them being 125° of Fahr. but most of them rise out of the sand, in the sea a few yards from the shore; they are so numerous that every wave, although it blows fresh, is very warm to the hand. Along with the water, a great quantity of sulphuretted hydrogen gas is emitted. The ruins of ancient baths still exist here, and near them a part of an inscription, with the name Diagoras. Now if the eruption had taken place since the time of that philosopher

(about 400 years before Christ), we should probably have had some records of it; therefore it is fair to presume that the Catacombs are of more ancient date. I obtained an ancient Greek vase taken from one of these sepulchres, which has all the characters of the very earliest period of the arts.

The island is still subject to frequent earthquakes; and probably it was an exertion of this volcano, or of that at Santorini, which destroyed one of the principal towns of Candia or Crete, with its inhabitants, in the year 1809.

About four miles to the north-east of Milo is Polino (or Burnt Island), which consists entirely of one immense cinder, with a central hill composed of a smooth-fractured, compact, baked clay, of a dusky white colour, appearing like a heap of pottery, and the highest point being about 500 feet above the sea. To ascend this hill, it is necessary to pass along a ridge, of which there are eight, that support the central mass. The intervals of these ridges form ravines of pumice stone. The island is uninhabited, and entirely without fresh water, which is not the case with Milo, where there are springs of good water, Upon ascending the hill of Polino, I observed some modern excavations, like mines, but there is not any apparent metallic substance that could have been followed, and they extend about 20 yards into the hill, showing the invariable volcanic formation of the island. There are here no remains of ancient ruins, and there is scarcely any vegetation.

ARTICLE VIII.

An Examination of the Blood. By J. L. Prevost, MD. and J. A. Dumas.*

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THE authors commence their memoir with observing, that the previous microscopic examination of the blood had proved that this fluid during life is merely serum, holding small regular insoluble corpuscules in suspension. These corpuscules are always composed of a central colourless spheroid, inclosed in a red coloured membrane, from which it readily separates after death. This white central spheroid is transparent and spherical in those animals which have circular particles, and oval when the particles are elliptical In the first case its diameter is constant; in the second, various. The colouring matter is readily divisible, but insoluble in water, and always separates from it by standing. The three substances which are examined in the chemical

• Abstracted from the Annales de Chimie et de Physique, tome xxiii. p. 50.

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