Apkil 3, 1SS5. 1 



SCIENCE. 



273 



covered with trees and shrubbery ; that tidal 

 observations in the lagoon show no relation 

 between the rise and fall inside the lagoon, 

 and outside ; that the weather, though mostly 

 fine, is somewhat changeable, with occasional 

 sudden showers ; and that the climate of the 

 island, though warm, is delightful, the sur- 

 rounding sea conducing to an equable tem- 

 perature. 



Mr. Upton presents a very full paper, occu- 

 pying nearly one-third of the volume, on the 

 meteorolog}' of the island during the period of 

 two weeks extending from April 25 to May 9. 

 Frequent observations were made with the 

 ordinary meteorological instruments, and with 

 special radiation apparatus furnished by the 

 chief signal-officer. The meteorological bear- 

 ings of the eclipse were carefully attended to, 

 and the observations are fully discussed, and 

 the results clearly presented in graphical form. 



One section of the report was prepared b}' 

 Professor Trelease, and relates to the botairy 

 of Caroline Island as represented b} r the col- 

 lections of Dr. Dixon, U. S. navj^, who con- 

 tributes also a page or two of interesting notes 

 on the zoolog} T of the island. The lepidoptera 

 received attention, and the valuable collection 

 made b}~ Dr. Palisa was taken to Vienna for 

 identification. At Professor Holden's 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 first 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-mercurial 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 necessary to devote an 

 observer and a telescope to the further prose- 

 cution of this search." Dr. Hastings, with an 

 unusual equipment for polariscopic 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 change of the moon's 

 place, precludes the explanation hitherto ac- 

 cepted of a gaseous atmosphere extending as 

 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 thorough 

 review of the results of all the observations of 

 the corona at previous eclipses, and groups 

 them under the head of spectroscopic analysis, 

 polarization, and photography. 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 BRAZIL. 1 



The greater part of the empire consists of an ele- 

 vated plateau, having the mean elevation of from 300 

 to 1,000 metres, limited on the north and west by the 

 great continental depressions of the Amazonas and 

 Paraguay basins, which are almost united through 

 the valley of the Madeira, and its tributary the 

 Guapore'. A portion of the elevated plateau of 

 Guiana, nearly the whole of the great Amazonian 

 depression, and the upper part of that of the Para- 

 guay, are also included in the empire. In addition 

 to these four grand natural physical divisions, there 

 is also an Atlantic border-region, forming a narrow 

 strip between the ocean and the eastern margin of the 

 great continental plateau. 



Although generally represented as wholly moun- 

 tainous, the Brazilian plateau consists in great part 

 of tablelands, which, from the deep excavation of 

 the innumerable river -valleys, have become very 

 much accidented, so as to present a mountainous 

 aspect. The true mountains (restricting the term 

 to the elevations formed by upheaved strata) are 

 mainly in the eastern and central portions, and may 

 be considered as constituting two groups, nearly 

 separated by the elevated tablelands of the Parana 

 and Sao Francisco basins. 



n 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 Sao Roque, to or near the southern 

 limits of the empire. The central or Goyaz group 

 occupies a part of the southern portion of the province 

 of Goyaz, 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, across the southern 

 portion of the province of Minas Geraes. This trans- 

 verse ridge, with the mountains of Goyaz, forms part 

 of the great east and west watershed of the con- 



1 From the Rio yews. 



