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in consideration of the greater thickness of the layers as a younger tree? The only direct data I possess bearing on this point are derived from a piece of a transverse section, 3} inches deep, of a “rail' which the exhibitor says was taken from the trunk at the height of 275 feet from the ground. As its layers, on a breadth of nearly seven eighths of an inch, show only a slight perceptible curvature, it must have come from a part of the trunk still of several feet in die meter. On this section the exterior inch, nearly all alburnum, contains 90 layers; the next, 60; the next, 45; the remaining half-inch, 16, making 32 to the inch. That the exterior layers should be thinner at this height than those near the base of the tree, is just what would be expected. If we apply this ratio of decrease of the number of layers to the inch as we proceed inwards, to the section at twenty-five feet from the ground, we should, at four inches within that part of the circumference which I have examined, have only 17 layers to the inch, which, taken as the average thickness, would make the tree only 1034 + 24 = 1058 years old. But it is not probable that the thickness of the layers increases so rapidly. The data we possess on other trees go to show that a tree, after it is 400 or 500 years old, increases in diameter at a pretty uniform rate for each twenty additional years, on the whole, although the difference in the thickness of any two or more contiguous layers, or of the same layer in different parts of the circumference, is often very great. Still, when we consider how very much thicker are the annual layers of a vigorous young than of an old one, perhaps we should not be warranted in assuming more than the average of 17 layers to the inch for the whole section.

“Some useful data may be obtained from a tree more nearly related than any other to the two California ones, though of a different genus, namely, the so-called Cypress of our Southern States (Taxodium distichum). I possess three sections of different trees of Taxodium, reaching from the centre to the circumference. One of these, on an average radius of 27 inches, exhibits 670 layers; a second, on a radius of 30 inches, has 525; a third, on a radius of 22 inches, has 534 layers. The average is 576 layers to a semidiameter of 26 inches, or about 22 layers to an inch. Half of this growth (13 inches radius) was attained at the close of the first century ; while the exterior layers of the oldest specimens were only the fiftieth or sixtieth of an inch in thickness. We have reason to believe, therefore, that

the Wellingtonia (as it is called) of California is at least as rapid in its growth as the Taxodium. We may safely infer, I think, in the absence of other data, that when the tree in question had attained the size of 26 inches in semidiameter, it was only 576 years old. If thereafter we suppose it to have increased at the intermediate rate of 35 layers per inch for the next 26 inches, and at the actual rate of the last century (as ascertained by inspection), namely, at 48 layers per inch, for the remaining 10 inches, we should assign to it the age of 2,066 years as its highest probable age. I think it more likely to be shown, when the wanting data are supplied, that the tree does not antedate the Christian era. There are said to be eighty or ninety such trees, of from ten to twenty feet in diameter, growing within the circuit of a mile from the one felled. When the next of these venerable trees is wantonly destroyed, it is to be hoped that its layers will be accurately counted on the whole section, and the thickness of each century's growth carefully measured on the radius.

“ The tree in question is a near relative of the Redwood of California, namely, the Taxodium sempervirens of Don, of late very properly distinguished as a separate genus under the unmeaning and not euphonious name of Sequoia, - á tree now growing in England, and sparingly also in our own vicinity, where it is barely hardy. My friend, Dr. Torrey, has for nearly a year possessed specimens of foliage of this tree, which he took to be a new species of Sequoia. The fruit and branches of the juniper-like foliage (probably only one form of a dimorphous foliage, which is common in Cupressinea) having been received in England from Mr. Lobb by Dr. Lindley and Sir William Hooker, they have recognized in this tree the type of a new genus distinct from Sequoia, to which the former has given the name of Wellingtonia. The wood is, I believe, much the same as that of the Redwood, which tree also attains a gigantic size. The principal characters yet ascertained are that the cones of Wellingtonia are oblong, and have a thick woody axis. Additional materials are needed to confirm the genus, if such it be.”

Mr. Paine made the following communication on the approaching eclipse of the sun :

“ On the afternoon of Friday, the 26th of May next, there will be an eclipse of the sun visible and generally large throughout the United States, and actually annular in part of the Territories of Washington

VOL. III.

13

and Minnesota, of Vancouver's Island, of Canada West, and of the States of Michigan, New York, Vermont, New Hampshire, Maine, and Massachusetts.

“ A central, or very nearly central, solar eclipse, at any place, is indeed of rare occurrence. At the city of Paris only one takes place in the 133 years between 1767 and 1900, and although in Boston we have been more favored than Paris, the phenomenon in the century and a quarter between 1775 and 1901, and perhaps many more years, occurs here but four times; namely, in the annular obscurations of April 2, 1791; May 26, 1854 ; and September 28, 1875; and in that which was total, on June 16, 1806. The eclipse of February 12, 1831, was also annular at Nantucket and at Chatham, Cape Cod, but not elsewhere in New England.

“ From computations, the results of which are more particularly given below, it appears that the path of the central eclipse of the 26th of May first enters upon the earth in the North Pacific Ocean near the Caroline Islands, in Lat. of about 61° North, Long. 197° West ; thence taking a northeasterly direction, it touches our continent near Cape Flattery in Washington Territory; it thence passes over Vancouver's Island, British Oregon, Minnesota, Isle Royale, Lake Superior, Canada West, New York, Vermont, New Hampshire, and Maine, to the Atlantic, where it leaves the earth in Lat. of about 36°, Long. 52°, having in 3h. 41m. 21", the time of its continuance thereon, run over 145} degrees of longitude and 56 of latitude.

“ It, moreover, appears that the duration of the ring, where central, in Washington Territory, is four and a half minutes, (which is nearly its longest duration at any place,) and in New York and New England somewhat less than four, although the ring is about ten seconds broader, and the distance between the lines of the northern and southern limits of the annular phase about thirty miles greater in the northeastern than in the northwestern part of the United States.

“In the Northeastern States, these limits will be well represented by lines drawn on a map, one from the southwestern part of the island of Montreal, over the southern part of the towns of Gardiner and St. George in Maine, to the ocean, and another from Ameliasburg in Canada West, over Ellisburg and Saratoga Springs in New York, Bennington, Vt., Leyden, Sterling, Dedham, Marshfield, and Orleans, in Massachusetts. These lines will be nearly parallel, and distant about 145 English miles, and will include between them the northeastern part of New York, nearly the whole of Vermont, all but the northern part of New Hampshire, the southwestern part of Maine, and, in Massachusetts, the northeastern part of the counties of Franklin, Worcester, Norfolk, Plymouth, and Barnstable, nearly the whole of Middlesex, and the whole of Suffolk and Essex. A third line, drawn nearly equidistant between the two others, from the southern part of Isle Royale in Lake Superior to Ogdensburg, N. Y., thence over Middlebury, Vt., Hanover, Sanbornton, Gilmanton, and Rochester, N. H., to the ocean at Cape Neddock in York, Maine, will represent the path of the central eclipse ; as a fourth, from Gibraltar Point, near Toronto, C. W., over Delhi and Kingston, N. Y., Middletown, Conn., to Block Island, R. I., will that of the line of eleven digits of obscuration on the north limb of the sun.

" As sixty-three years have passed since the occurrence of the last annular eclipse in New England, and as in the last forty-six years of the present century only one more will take place, it is not doubted that the one of May 26th will be viewed with interest by every spectator ; but it is hoped that those observers, within the limits of the ring, who may be provided with a good telescope, will give particular attention to the singular appearances which so often have been noticed at the second and third contacts, and which, in consequence of having been minutely described by the late Mr. Bailly, are known by his name, especially as there is some reason for the suspicion that these beads, &c. may be seen or not, at the pleasure of the observer, according as he employs a screen colored red or green.

“ In the eclipse of February 12, 1831, which was viewed by the writer at the light-house on Monomoy Point, off Chatham, with a red screen, these beads were, just before the formation of the ring, so very conspicuous, that it was difficult to determine with precision when it actually took place, whilst in that which was annular in Washington in September, 1838, and that which was total near Savannah in November, 1834, these appearances could not be perceived by him, although carefully looked for through a screen composed of two glasses, one shaded light red, the other light green.

“ Indeed, it is particularly desirable that at some places there will be two observers furnished with telescopes of nearly the same optical power, but with screens colored green and red, who, after the second contact, shall exchange their instruments for their observations on the third, and shall note carefully the appearances and phenomena by which each contact is attended.

“ The elements of the moon used for the following computations (except the parallax and semidiameter) are the mean of the quantities deduced from the tables of Damoiseau and Burckhardt. Those of the latter were taken from the English and French Nautical Almanacs, but those of Damoiseau were computed for May 26th, 6, 8, 10, and 12 hours of Paris, and thence interpolated for every hour of the meridian of Greenwich. Whilst the difference of the tables in latitude is small, or about a second and a half, in longitude it is very considerable, or eleven seconds. For the parallax, that of Burckhardt was preferred, as corrected by Mr. Adams, one of the distinguished discoverers of the planet Neptune, who, in a memoir affixed to the Nautical Almanac for 1856, appears to have thoroughly investigated the subject.

Path of the Central Eclipse of the Sun over the Earth, Friday, May

26, 1854, according to the Tables of Damoiseau and Burckhardt, for every Fifth Minute whilst crossing the North Pacific Ocean, and for every Minute of the Remainder of the Time of its Continuance on the Earth.

Mean Time at Greenwich.

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