June 1, 1891.] 



KNOWLEDGE 



111 



few such small exceptions, the book is exceedingly simple 

 as well as amusing. 



The Autiihiixiniphii -/' tlic luiitli : A /lopular account of 

 (Tcoloi/irdl llistiin/. l!y the Kev. II. N. Hutchinson, 

 B.A.,' F.G.S. (Edward Stanford, London, 1890). There 

 is a scarcity of popular works on Geology which can be 

 relied upon as giving accurate information in simple 

 language. This book has been very conscientiously written. 

 It gives a brief sketch of the principal geological periods, 

 and endeavours to explain briefly the methods by which 

 the conclusions of geologists have been arrived at. 



Monoyniph of tlw British Cicada. Part V. By G. B. 

 BucKTON, P.E.S. (Macmillan & Co.) This part contains 

 the Acoccjihiiliihr and the first two genera of the .hissithc. 

 There is also a useful chapter on the parasites of the 

 Cicadie, for which no hint of apology was necessary, for 

 in our opinion it is just the discussion of side issues such 

 as these that, next to the figuring of the species, consti- 

 tutes the chief niison d'etre of the work. The parasites 

 of the Homoptera have been so little studied in this 

 country that all available information will be welcomed by 

 students of the order. The most interesting subject 

 noticed in this connection is the investigations of Prof. 

 Mik and others into the nature of the black oval objects 

 which so often disfigure the bodies of the Jussidce and 

 'Tijl)hl<)ei/hid,r. These have been proved to yield hymenop- 

 terous parasites belonging to the extraordinary ant-like 

 genus (Tonatoinis, but many points in the life-history of 

 the parasites still need elucidation, and it is to be hoped 

 that Mr. Buckton's summary of results may lead others 

 to take up the subject. The coloured plates are not all of 

 equal merit, and the figures of one insect at least, the 

 handsome and brilliant I'lKtiiiiietiiiiiux, suffer from the 

 unusual defect of being insufficiently coloured. 



Xaturc's Wonder-Workerti. By Kate R. Lovell. (Cassell 

 & Co.) Another book on the inexhaustible theme of 

 insect life and habits. Though the authoress does not 

 profess to write in other than a somewhat popular style, 

 her work is carefully done, and shows an avoidance of those 

 blemishes of style that too oiten disfigure works of this 

 sort. Into 280 agreeably written and neatly printed pages 

 has been collected a considerable fund of information, for 

 the most part accurate, about some of the familiar insects 

 that more or less directly aft'ect the welfare of mankind. 

 The book is most attractively got up and illustrated with 

 abundance of woodcuts, which are full of life and vigour, and 

 portray many and varied phases of nisect Ufe. 



/)'// 'I'nicl; (did 'rniil : a JdUrnci/ throin/Ii Canada. Bv 

 Edwaui) Koper, F.R.G.S. ( W. H. Allen kCo., 1891.) The 

 author of this chattily written book makes no pretensions 

 to be a naturalist or scientific traveller, but he is an artist 

 with an eye for birds and beasts, as well as for the grand 

 scenery of the north-west. He introduces his readers in a 

 realistic way to a wide range of country extending from 

 the .\tlantic to the Pacific, and to many types and conditions 

 of men, taking us through the great wheat-growing country 

 to prairie ranches and the canons and passes of tlie Eocky 

 Mountains on to British Columbia. His picture of a Chinook 

 village (m (,)u('on Cliarlottc's lsl:iiiil, namcil Skidegate, shows 

 the gigantic carved posts which these Indians erect in front 

 of their houses. Speaking of these totem posts Mr. Roper 

 says, " I had always been under the impression that the 

 totem was hold sacred by the tribe or family possessing it, 

 and that they would not injure or allow to be injured the 

 object chosen as the symbol of their tribe ; but at Skidegate 

 their totem is the shark, yet this family of Indians are famous 

 shark slayers, killing them for profit." The houses of these 



Indians are most substantial wooden framed structures, 

 sometunes forty feet long and equally deep — the walls and 

 the roof are made of split slabs of cedar. It is surprising 

 what immense beams and posts they use for these houses. 

 When an Indian wishes to build a house he gets up a " bee." 

 Calling the members of his tribe together he distributes 

 presents amongst them, which are called " potlaeh." They 

 set to work with a will, drawing and fitting together great 

 logs until the house is completed. One of the most striking 

 features of these Indian villages are their totem posts, which 

 are sometimes three or four feet in diameter and forty feet 

 high. They are carved with great grotesque faces and 

 figures and a representation of the animal representing the 

 clan. Mr. Roper likens the posts to a family coat-of-arms, 

 which also records incidents in the familv historv. 



THE COAL-SACK REGION OF THE MILKY WAY. 



By a. C. Ranyard. 



NEAR to the foot of the Southern Cross there is a 

 dark patch or hole in the Milky Way which was 

 named by the early English-speaking navigators 

 of the Southern Seas '• The Coal-Sack," on ac- 

 count of its blackness as compared with the sur- 

 rounding region. It is so striking an object in the Southern 

 skies that even the Australian natives seem to have noticed 

 it. It is stated, on the authority of a paper read before the 

 Royal Society of New South Wales,'- that this black patch 

 figures in Australian folk-lore as the embodiment of evil in 

 the shape of an emu who is lying in wait for an opossum 

 that has climbed into the branches of a tree represented 

 by the stars of the Southern Cross. 



The physical meaning of this dark area in the midst of 

 a closely star-strewn region has long been a subject of 

 speculation. It has generally been described as some 

 8'^ or 10° long by 5° or 6° wide, with sharply-defined 

 borders, and as perfectly devoid of stars. Proctor rejected 

 as highly improbable the idea that there could be a tunnel 

 directed towards the earth through a great thickness of stars, 

 and accounted on his stream theory of the Milky Way for 

 the dark patch as an opening where we look into distant 

 space between two branches of the great galactic stream 

 of stars, which he conceived to be a stream of roughly 

 circular section. In an article on the Coal- Sack Region, 

 published in Knowledge for May 1st, 1886, p. 225, he asks 

 the reader to consider whether it can be "an accident 

 that over this large dark space, covering about 50 square 

 degrees, there is not a single lucid star, while all around its 

 borders lucid stars are strewn in plenty '?" The whole 

 surface of the heavens, he remarks, " exceeds the Coal- 

 Sack some eight hundred times in extent ; and as there 

 are about GOOO lucid stars, one might expect seven or eight 

 such stars to be found in the Coal- Sack. But this is iar 

 from being all. The neighbourhood of the Coal-Sack is 

 much richer in lucid stars than other regions in the 

 heavens ; so that it is just where stars should be most 

 richly distributed that this vast black spot makes its ap- 

 pearance." The question whether the absence of naked 

 eye stars from the Coal- Sack Region and their presence in 

 great abundance in the Milky Way Region around can be 

 a mere coincidence can hardly be regarded as doubtful, and 

 every tlioughtful person will acknowledge that the observed 

 distribution tends to show an intimate connection between 

 the naked eye stars and the distribution of the smaller stars 

 or nebulous matter, which gives rise to the hazy stream of 

 light wo know as the Milky Way. 



• Sec Miss Clerke's Si/stem of the Stars, p. 356. 



