558 



NATURE 



[June 22, 191 1 



jjidMi in-, .iini ill -^I.ir liii;^ jjuinK 



lor t\jM I iiiiinl.il 1' 



i iic iiiJIitN ol iii(;isun-iiiiiit> (li till- ll•ll^ile slrt-ngth 

 cil t;il)ric^, \>t ^lillll-^i(ln dt )i\dr<.-cii iliroiij^h mem- 

 branes, ;iiul (il a scaii'li tor li<,^ln all(.}>, aM- ton obvious 

 t(i ncid liirtliiT idinmiiil, and ;la- I.Hiii.tii pages of 

 \\v liisi report doaiiiii; uith these questions are con- 

 li-r aiui to the poiiu. 



If there is one conclusion to be derived from a 

 study of these reports it is that a serious mistake 

 was made \cais ai^o ulicn in America tlu- L;rant for 

 the late Dr. S. I', l.ani^hy'- t.N.periments w.is wiili- 

 drawn. If tin- w < >i k now being done doe^ not aho- 

 j^ctiifr niakr \\\) ilu di licitncies caused by neglect in 

 the i)ast, il is gratilying to learn that experiments 

 an pioi^iessing in this direction. 



Ill a recent review of a translation by the editors 

 of The Aeronautical Journal, the suggestion was 

 made that they might well bring out further books on 

 aviation. "The Aeroplane" provides in a small com- 

 pass a summary of the general principles involved 

 in aviation, and the hope expressed by the authors 

 " that the book will find a sphere of usefulness as a 

 comprehensive introduction to the latest and the most 

 fascinating of sciences ** is well supported by an 

 examination of the contents. The first chapter deals 

 with properties of the air, including meteorological 

 considerations and relations between pressure tem- 

 perature and density. The next two chapters are 

 devoted to the flow of air round variously shaped 

 bodies, its pressure on plane and curved surfaces, 

 formulae for the centre of pressure, and lift and drift. 

 Then comes a study of gliders, in which the reader 

 is asked to make a few experiments with a sheet of 

 paper; stability and steering next follow. In the 

 chapter on propulsion the main notions regarding 

 "pitch" and "slip" are clearly defined. If the 

 authors prepare a revised second edition they might, 

 however, point out a little more clearly that a limit 

 to the efficiency of screws is afforded by the fact that 

 to obtain the maximum thrust there must be no for- 

 ward motion, while if there is no slip there is no 

 thrust. The next chapter deals with the leading pre- 

 sent-day monoplanes and biplanes, giving their dimen- 

 sions and advantages. Under " Navigation " great 

 emphasis is laid on the importance of the parallelo- 

 gram of velocities, though not called by that name, 

 and stress is laid on the impossibility of finding the 

 way when the earth is invisible, owing to winds. The 

 last chapter, on "Motors," extends from the simple 

 elastic to the gnome, and the bibliography, glossary, 

 and tables will be found useful. But is there any 

 glossary that contains all that is needed? "Angle of 

 attack," "bent-up wings," and "single- and double- 

 lifting aeroplanes " should certainly be recognised, or 

 better terms substituted by the Aeronautical Society's 

 committee. And are Mr. "Hubbard and his colleagues 

 correct in defining " angle of incidence " as the angle at 

 which a plane is inclined to the horizontal? More- 

 over, the entry occurs, '"Pressure. — See Resistance"; 

 but resistance is not to be found. 



In the third collection of papers and translations 

 issued under the title of "The Mechanics of the 

 Earth's Atmosphere," Dr. Cleveland Abbe has con- 

 tinued the task he has for some time been under- 

 taking of introducing English-speaking students to 

 the rapidly increasing literature that has arisen out 

 of the efforts to break down the line of demarcation 

 between meteorology and physics. The earliest appli- 

 cation of the notions of mechanics to the earth's 

 atmosphere in the present collection is Hadley's paper 

 ^^ 1735.. on the cause of the trade winds. The study 

 of rotational effects is next taken up in the papers of 

 Poisson (1837), Tracy (1843), Braschmann and Erman 

 NO. -2173, VOL. 86] 



>, (18S1;, (jorodensky (1904). Kerbtr's 

 i . ihe limits of the aimoi»phere is now 



reprinted in view of the interest attaching to the sub- 

 ject arising out of explorations with sounding balloons. 

 I 111 iranvliii.n ot Guldberg and Mohn's sti 

 1 1. s;!. Nil i- due to Prof. Frank Waldo. We 1 ■ .• 

 ha\c a series of papers by Von Bezold, dealing with 

 ilu; thermodynamics of the atmosphere and other con- 

 siderations, and dating from 1892 to 1906, and, finally, 

 the two memoirs of Margules (1901 and 1904), which, 

 a- ihi- editor jioinis out, introduce us to the great 

 |)idlil<nis oj ilu- future that is, the thermal trans- 

 formations of energy persistently going on in the 

 atmosphere. The collection might with advantage 

 form the subject '' ' ~ -<"s of lectures in our univer- 

 sities, and the > which the subject presents 

 for original work n. .;- numerous as they are intri- 

 cate and complex, ihe studenjt,^ will be glad to have 

 such a collection of literature rendered so easy of 

 access. 



THE SEA DYAKS OF BORNEO. 



IT is obvious that this pleasantly written book is not 

 intended for the anthropologist, but is rather meant 

 for that large class of readers who take a general 

 interest in remote countries and strange peoples. 

 Nor is Mr. Gomes in any special sense himself an 

 anthropologist, a matter it is well to mention, since 

 in some reviews considerable stress has been laid on 

 the fact that no mention is made of the so-called 

 nyarong, the " spirit helper " of the Dyaks. But even 

 if the nyarong, or, as it should be spelt ngarong, is 

 not mentioned by name, its existence is not ignored ; 

 an undoubted example will be found on p. 188, and it 

 may be assumed that the reference to a Dyak of 

 whom it is recorded on p. 143 that "he treated a 

 snake with the greatest kindness, because it had been 

 revealed to him in a dream that the spirit of his 

 grandfather dwelt in that snake," is another example 

 of the same belief. 



With the possible exception of the Kenyahs, the Sea 

 Dyaks are the most companionable and pleasant race 

 in Sarawak, and it is clear that the author has en- 

 joyed so considerable a measure of their friendship 

 and confidence that, had he but possessed the neces- 

 sary knowledge, he would have been able to write a 

 book of great ethnological value. The work is thus 

 one of the strongest arguments in favour of the pre- 

 liminary training of missionaries that has fallen into 

 our hands, for it is clear that its weaknesses are due 

 to nothing but the author's lack of knowledge of 

 where and how to look for information, since every 

 page indicates his interest in his people and the 

 trouble he has taken to know them. 



The honesty and truthfulness of the Dyaks are 

 described and illustrated by the tugong htila, the 

 "liar's mound," which, once started, seems to persist 

 long after the liar it commemorates is himself dead. 

 A pile of branches is heaped up in memory of the man 

 who has uttered a great lie, so that future genera- 

 tions may take warning. The persons deceived start 

 the tugong hula by piling up the branches in some 

 conspicuous spot by the side of the path from one 

 village to another. Every passer-by contributes to it. 

 and at the same time curses the man in memor}' of 

 whom it is raised. " Once started, there seems to be 

 no means of destroying a tugong hula. There used 

 to be one by the side of the path between Seratok and 

 Sebetan. As the branches and twigs that composed 



1 " Seventeen Years amone the Sea Dyaks o; Borneo." By E. H. Gomes, 

 and an introduction by the Rev." J. Perham. Pp. 343. (London : Seeley 

 and Co., Ltd., igti.) Piice i6s. net. 



