24 



NATURE 



[March 4, i^^P 



of the image can easily be shown to be of the same 

 order as DE ; whence the angular area of the image 

 is, say, one-millionth of the area of AB ; and since 

 no optical arrangement can increase the surface bril- 

 liancy of an image, the latter is fifteen magnitudes 

 fainter than AB, and therefore utterly invisible. 



It is only when two stars approach each other 

 so closely that their discs are almost in contact that 

 :any sensible Einstein effect occurs ; and since the 

 two discs are in this case absolutely inseparable, the 

 visible effect would be simply a slight brightening. 

 In view of (i) the rarity of such close appulses, (2) the 

 impossibility of predicting them, and (3) the transient 

 nature of the brightening, which would last for only 

 a few days, the prospect of detecting such a pheno- 

 menon is very small. 



The outburst of novae cannot be explained in this 

 manner, as some have suggested, for it could not 

 -possibly produce a ten-thousandfold increase in light; 

 moreover, the light-curve before and after maximum 

 would be exactly symmetrical, which is assuredly not 

 the case with novae, the increase of light being much 

 -more rapid than the decline. 



It is to be noted that even if some brightening were 

 <ibserved in an aooulse. it would be impossible to sav 

 whether the liij^ht-bending followed the Newtonian cr 

 -the Einstein law\ A. C D. Crommelin. 



The New Zealand Institute. 



THE publication of the fifty-first volume of the 

 Transactions and Proceedings of the New 

 Zealand Institute marks the commencement of a new 

 epoch in the history of that very vigorous scientific 

 organisation. The volume itself compares very 

 •favourably with those of past years, and its contents 

 show that there is at least one part of the British 

 Empire where pure science is being cultivated as 

 strenuously as before the war. We are glad to see 

 that the institute is receiving more support from the 

 New Zealand Government, while the large member- 

 ship of the nine constituent societies scattered through- 

 out the Dominion clearly indicates the influence which 

 1t is exerting upon the New^ Zealand public. 



The volume opens with obituary notices and por- 

 traits of three distinguished New Zealanders — 

 Alexander Turnbull, who devoted his leisure to the 

 ■collection of a magnificent library, bequeathed to the 

 Dominion, including 32,000 bound volumes, dealing 

 especially with the history of the Pacific^ Islands; 

 Henry Suter, known throughout the scientific world 

 as a distinguished student of conchology, and author 

 •of the " Manual of the New Zealand Mollusca " ; and 

 Thomas Adams, who did great work for his adopted 

 country in the promotion of scientific arboriculture. 



Of the numerous original memoirs which the 

 volume contains, it is not too much to say that thev 

 •embody a large amount of information of hii?h 

 scientific value, and if they relate almost exclusively 

 to matters of local interest, dealing- chiefly with the 

 fauna, flora, and neology of the islands, this is onlv 

 as it should be. for it is" in these fields that the New 

 "Zealand man of science finds his magnificent oppor- 

 tunities. Where there is so much to choose from it 

 "is difficult to single out particular contributions for 

 notice, but the attention of zoologists should be directed 

 to the very interesting discovery of a second species 

 of New Zealand frog, Liopelma Hamiltoni, found bv 

 Mr. Harold Hamilton on Stephen Island, in Cook 

 Straits, and described (with excellent coloured illus- 

 trations) by Mr. A. R. McCulloch, of the Australian 

 Museum. This species is closely related to the long- 

 1<nown but rare Liopelma Hochstetteri of the North 

 Island, the only previously known New Zealand 

 NO. 2627. VOL. 105] 



amphibian. In the botanical field Dr. J. E. Hol- 

 loway continues his admirable studies on the genus 

 Lycopodium, while geology is well represented by 

 papers by Dr. P. Marshall, Mr. R. Speight, and 

 others. In the department of geophysics Mr. A. W. 

 Burrell contributes a very interesting account of a 

 working model to demonstrate the manner in which 

 ocean currents may be caused by the rotation of the 

 earth. 



In conclusion, we may note that the institute has^ 

 decided to elect a body of fellows, limited to forty in 

 number, who are to have the privilege of writing 

 after their names the letters F.N. Z.Inst. — a distinction 

 which we do not doubt will have a real value in the 

 world of science. 



The Geology of the West Indies. 



EARLY in 1914 Dr. T. Wayland Vaughan, of the 

 United States Geological Survey, paid an official 

 visit to several of the smaller West Indian islands, 

 partly with help from the Carnegie Institution of 

 Washington. Besides studying the stratigraphical 

 geology of the islands and making notes on their 

 physiography, he also collected large series of fossils 

 which were sent for detailed examination to Washing- 

 ton. He thus obtained material for a valuable con- 

 tribution to our knowledge of the Tertiary sedimen- 

 tary rocks which form the greater part of these 

 islands, and made possible satisfactory comparisons 

 with the corresponding geological formations of the 

 southern United States. Dr. "Vaughan has already 

 published several preliminary notes on his results, and 

 an especially important memoir on some fossil corals 

 and the formation of coral-reefs. His final report, 

 however, on the details of local geology and the 

 general conclusions are deferred until all the fossils 

 are examined and described. He has just edited a 

 series of these descriptions, which has been pub- 

 lished by the Carnegie Institution (Publication 

 No. 291, 1919) in a small volume illustrated by 

 beautiful photographic plates. 



Calcareous algae from the Eocene limestone of St. 

 Bartholomew and from the Oligocene limestone of 

 Antigua and Anguilla are described by Mr. Marshall A. 

 Howe. Lithothamnium and related forms are well 

 illustrated bv enlarged sections. The Foraminifera 

 are not onlv described with excellent figures bv Mr. 

 J. A. Cushman, but also discussed from the geological 

 jDoint of view. Some of the larger orbitoid species 

 make correlations possible with corresponding _ rocks 

 both in continental America and in Europe, while the 

 small Miocene species allow very definite correlations 

 with Panama and the coastal plain of the United 

 States. The Brvozoa, described by Drs. F. Canu and 

 R. S. Bassler, "are of Upper Oligocene and Lower 

 Miocene age, and notes are added on the distribution 

 of those species which occur in other parts of the 

 world. The Eocene and Oligocene mollusca, described 

 by Mr. C. W. Cooke, are of great geological import- 

 ance, and comoarisons are facilitated by faunal lists. 

 The account of the Decapod Crustacea, by Miss 

 Mary J. Rathbun, is almost entirely new, only two 

 species of one genus (Ranina) having previously been 

 recorded from the Tertiary formations of the West 

 Indies. A few genera are distinctively American, but 

 some have close afiinitv with those at present living 

 in the Indo-Pacific region. 



We congratulate Dr. Wayland Vaughan and his 

 colleagues on the thoroughness with which thev are 

 accomplishing their task, and we look forward to 

 the publication of the concluding sections of this great 

 contribution to the geology and palaeontology of the 

 Central American region. " 



