Nov. 4, 1875J 



NATURE 



Nebraska; its Advantages, Resources, and Drawbacks. 



Illustrated. By Edwin A. Curley. (London : Sampson 



Low and Co., 1875.) 

 j\Tr. Curley acted as the Special Commissioner of the 

 Field to the emigrant fields of N. America, and the pre- 

 sent work appeared originally, we believe, as a series of 

 papers in that journal. Mr. Curley has evidently done 

 his work as Commissioner thoroughly, and the present 

 volume is an almost exhaustive account of Nebraska from 

 an emigrant point of view, and we would strongly recom- 

 mend all intending emigrants to study it carefully. The 

 author sets forth with perfect impartiality all the advan- 

 tages and disadvantages of Nebraska as a field for emi- 

 gration, with the result that for those who can command 

 a small capital, and are able and willing to do the neces- 

 sary work, there is every chance of success. Mr. Curley 

 describes the Geography of Nebraska, and has two chap- 

 ters of statistics. There is a chapter on the Climate, 

 two chapters on the Surface Geology, and one on the 

 Wild Fruits of Nebraska, by Prof. Aughey. In a series 

 cf chapters the author describes in considerable detail 

 the principal districts of the State, and has chapters on 

 Timber and Fuel, the Pastoral Capacities of the State, 

 Co-operative Colonisation, and Land. Indeed, the work 

 seems to contain answers to every inquiry that an emi- 

 grant is likely to make, down even to routes, steamship 

 lines, and fares. It is illustrated with many well-executed 

 woodcuts, lithographs, maps, and plans ; and even those 

 who have no intention of emigrating will find it pleasant 

 and instructive reading. 



A Series of Twelve Maps for Map-Drawins, and Ex- 

 amination. By Charles Bird, B.A., F.R.A.S., Science 

 Master in Bradford Grammar School. (London : 

 Stanford, 1875.) 

 The twelve maps are Europe, Asia, Africa, North ani 

 South America, England, Scotland, Ireland, France, 

 Germany, India, and Australia. They are simple out- 

 lines, showing the courses of the chief rivers, the run of 

 the mountains indicated by black lines, and the situ- 

 ation of the principal lakes. The maps, instead of 

 names, are covered with a large number of figures which 

 refer to a copious index at the end. The intention is, 

 that after the student has become thoroughly familiar 

 v.'ith the situations of the principal mountains, rivers, 

 towns, and other features of a country, his knowledge 

 should be tested by his being required to fill in, in these or 

 similar skeleton maps, the names corresponding to the 

 iigures furnished or pointed out by the teacher. It is also 

 intended to provide a handy method for drawing maps. 

 We believe that if judiciously used, the method here 

 indicated will be of good service for both purposes. The 

 maps are well drawn, and, so far as we have tested them, 

 accurately constructed. 



LETTERS TO THE EDITOR 



[ Tki Editor does not hold himself responsible for opinions expressed 

 by his carrespondents. Neither can he undertake to return, 

 or to correspond with the writers of, rejected manuscripts. 

 No notice is taken of anonymous communications. \ 



Observation of Cirrus Cloud 

 I HAVE just received from the Meteorological Observatory at 

 Upsal, Sweden, a number of blank forms (with instructions in 

 English) for observations of the directions of the cirrus cloud. 

 Copies of these forms I shall have much pleasure in supplying 

 to anyone who may be willing to make obiervations of these 

 clouds, the systematic and extensive observation of which is, as 

 you pointed out in a recent number of Nature, of such import- 

 ance in numerous meteorological inquiries. 



Alexander Buchan, Secretary 

 Scottish Meteorological Society, Edinburgh, Nov. 2 



Mr. Mallet's Paper on Prismatic Basalt 

 In a paper published in the Geological Alagazineio'c'it'^i&vi^&x 

 las% and entitled " Note on Mr. R. Mallet on the Prismatic 



Structure of Basalt," by Mr. Scrope, that author conceives he 

 has found a refutation of the explanation which I have given of 

 the production of the transverse joints in prismatic basalt in my 

 paper on the subject published in the Philosophical Magazine 

 for August and September 1875, and Proc. R. S. 158, 1875. 

 For this he appeals to the features presented by the transverse 

 joints in a group of three prisms stated to be from the Giant's 

 Causeway, existing in the hall of the Geological Society of 

 London. In one of these three prisms it is stated that the convex 

 surfaces of the two top joints point in opposite directions, so that 

 the upper articulation " is found to be biconcave in the fashion 

 of a double concave lens. In another of the prisms the convex 

 surfaces of the joints point downwards, while in the third the 

 convex surfaces point upwards." 



I will assume that these three prisms occupy the same relative 

 position with respect to each other vertically that they did whea 

 in situ, and that Mr. Scrope's description of the jointing is exact, 

 which, however, is not the case ; e.g. , the top surfaces of the three 

 prisms are not alternately concave and convex, but all are concave, 

 though in different degrees. The entire length of the prisms 

 referred to is about 4^ feet, and the group must have been taken 

 from a mass cooled both from above and below. The phenomena 

 presented by the joints of these prisms do not conflict with the 

 views which I have enunciated. The prisms referred to have 

 come from some portion of the original mass in which occurred 

 the dividing plane between that part cooled from the top and 

 that cooled from the bottom, as is proved by the existence in one 

 of the columns of a joint having surfaces curved in oppo- 

 site directions ; such plane, in fact, passing transversely through 

 the articulation said to be in the form of a double concave lens. 

 Other adjacent prisms may have their joints, within a limited 

 vertical height above or below this plane, either convex upwards 

 or downwards, for the slightest differences in the conductivity or 

 in the conditions and rates of cooling, will suffice either to 

 depress or to elevate in them, by a greater or less degree, the 

 plane already spoken of. It is also not difficult to see that 

 several alternations in the directions of the concave and convex 

 surfaces may occur in the neighbourhood of the meeting plane of 

 cooling in opposite directions, wheri, as in the case of other 

 divergent or opposite heat waves, more or less confusion in 

 normal structure must occur. 



I have not examined the group myself, nor should I c;re to 

 appeal to such fragments either in refutation or support of any 

 theory. Mr. Scrope's imaginary refutation appears to resolve 

 itself into a confirmation of the exactness of my views, and is 

 the product of his imperfect grasp of the physical conditions 

 involved in the question which he undertakes to discuss. That 

 Mr. Scrope has got but a very incomplete grasp of my views as 

 to the production of the cross-joints in prismatic basalt, is evident 

 from the inaccurate language in which he professes to describe 

 that portion to which he refers, as may be seen by those who 

 take interest enough in the subject to compare his note with my 

 paper [Philosophical Magazine for August and September 1875), 

 and more especially from p. 134 to p. 205. 



Oct. 18 RoBT. Mallet 



Plagiarism 



May I ask you to allow me a very small portion ot your space 

 to anticipate a charge of plagiarism which might otherwise be 

 made against my work on Cave-hunting, by the readers of the 

 article in the Z/'wwr^ /i'^wr, entitled "The Early Geography of 

 the British Islands, by Henry Walker, F.G.S., July 1874," 

 which I now see for the first time. 



In this ardcle there is a map (p. 423) so exactly like my own 

 that it is obvious that one is copied from the other, and it might 

 be believed (it has been suggested) that mine was taken without 

 acknowledgment from Mr. Walker, since his was published in 

 July, and mine in October, 1874- 



The facts are as follows :— In October 1871 1 published a map 

 in the Popular Science Rr^ie^v, and this is reproduced, with cer- 

 tain details left out, by Mr. W^alker, ^without allusion to my 

 previous publication. I repriated my map of 1871 in " Cave- 

 hunting." 



Now, I would willingly and heartily allow any map of mine, 

 in which the labours of others are combined with my own, 

 to be used ^by others without acknowledgment ; but that in 

 consequence of this I should be open to the charge of plagiarism, 

 as in this case, I do not feel justified in letting pass without a 

 word as to the facts. W. Boyd Dawkins 



City of Melbourne %.%., ofif San Francisco, Sept. 16 



