Page:Science vol. 5.djvu/297

 SCIENCE.

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��covered with trees and shiubliery: tlial tidul obsen'&tions io the lagoon show no relation between the rise and faU inside the lagoon, and outside; that the weather, though moatly fioe, is somewhat changeable, with occasional sudden showers; and that the climate of the blaud. though warm, is delightfiil, the sur- ronnding sea conducing to an equable tem- perature.

Mr. Upton presents a very full paper, occu- pying nearly one-thinl of Ibe volume, on the meteorol^}' of the island during the period of two weeks extending from April 25 to May 9. Fre<]uent observations were made with the ordinary meteorological instruments, and with Special radiation apparatus furnished by the 4^ief signal-officer. The meteorological beai'- ings of the eclipse were carefully attended to, and the observations ore fully discussed, and the results clearly presented in graphical form.

One section of the report was prepared by- Professor Trelease. and relates to the botany of Caroline Island as represented by the col- lections of Dr. Dixon, U. S. navy, who con- tributes also a page or two of interesting notes on the zoology of the island. The lepidoptera received attention, and the valuable collection made by Dr. Paliaa was taken to Vienna for identification. At Professor Holden'a request, however, he very kindly made and presented to the American expedition as complete a col- lection of duplicates as was possible; and these are reported upon by Mr. Butler of the British museum, and Mr. Strecker of Penn- sylvania.

Coming now to the physical and astronomi- cal results of the expedition, we find flrst a condensed statement of Professor Holden's plan of operations on the day of the eclipse, followed by the reports of all the observers on the special fields of work assigned to them. During the period of totality. Professor Hol- den devoted his own attention to the search for intra-mercui'ial planets, with the negative result long since known, and which he regards as conclusive to such an extent that ' ' at future eclipses it will not be necessarj- to devote an observer and a telescope to the further prose- cution of this search." Dr. Hastings, with an unusual equipment for pohiriscopic and spec- troscopic work, gave his entire time to the solar corona. He found that with delicate methods the brighter portions of the corona ought to be observable more than a minute before totality. Dr. Hastings presents his own observations, and concludes that "the enormous change in the extent to which the 1474 line could be traced east and west of

��the sun, with very slight cbimge of the moon's place, precludes the expUnatioo hitherto ac- cepted of a gaseous almoHphere extending aa far as implied by the spectroscope." Regard- ing these results, then, as strongly Indicating the need of a different explanation of the ob- served phenomena, he institutes a tboroui^h re^'iew of the resulla of all the observations of the corona at previous eclipses, and groups them under the head of spectroscopic analysis, poiarizatiou, and phot<^raphy. The hitherto accepted explanation of the phenomena is then briefly set forth; and following it his own ex- planation is proposed, which is, that the coro- nal phenomena may be fully accounted for by applying the well-known principles of diffrac- tion to the sunlight which grazes the edge of the lunar disk, and is propagated to the eye of the observer.

��THE PHYSICAL FEATURES OF BRAZIU

Tub greater part ot the empire consists of an ele- vated plateau, having ibe mean elevation of from 300 to 1,0(X) metres, limited on the north and west by the great continental depresslous oE the Amazonas nnd Faragaay basins, vhlcli are almost united through the valley of the Madeira, and its trlbutarr the GuBpore. A portion ot the elevated plataau of Guiana, nearly the whole of the great Amawminu depression, and the upper part ot that of the Para- guay, are also Included in the empire. In addltjan to these four grand natural physical divisions, there Is also a:i Atlantic border-region, forming a narrow atrip betwmn the ocean and the eastern margin ot the great continental plateau.

Although generally represented as wholly uioun- talnouB, the Brazilian plateau consists in great pari of tablelands, which, from the deep excavation of the innumerable river-valleys, have become very much accidenied, so as to present a mountalnoiu aspect, The true mountains (restricting the temi to the elevations Eonued by upheaved strata) are mainly in the eastern and central portions, and may be considered as consliluling two groups, nearly separateil by the elevated tablelands of the P:irand and Slio Francisco basins.

r The eastern or maritime group accompanies the coast of the Atlantic at a short distance from the sea, from near the north-east shoulder of the conti- nent at Cape Siio Roque, to or near the soatheni limits of the empire. The central or GoyaK group occupies a part of the southern portion of the province of Gnyaz, and that part of the province of Minas Geraes lying to the west of the Sao Francisco, and is joined to the eastern group by a transverse ridge ex- tending in the direction east-west, oeross the southern portion of the province of Minas Geroes. This trans- verse ridge, with the mountains of Goyaz, forms part of the great east acid west watershed of the cod-

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