November 22, 1894] 



NA TURE 



77 



jects. Besides several excellent series of examples, 

 a very useful summary is added to each chapter, 

 which will be serviceable for revision purposes. The 

 adoption of different sizes and kinds of type, when it is, 

 as here, carefully done, is also a very great boon to 

 beginners. 



The Sliiie-Rule. A Practical Manual. By Charles X. 



Pickworth, Wh.Sc. (London : Emmott and Co., Ltd., 



1894.) 

 The most modern form of slide-rule is of the Mannheim 

 or Tavernier-Gravct type, and undoubtedly surpasses its 

 predecessors in many ways. At the present time this 

 instrument is in general use on the continent, principally 

 in France and Germany, and it is now becoming more 

 popular in England. 



The slide-rule may be defined as an instrument for 

 mechanically effecting calculations by logarithmic com- 

 putation. By its aid arithmetical, algebraical, and 

 trignometrical processes may be performed much 

 more quickly and with greater ease than by the 

 ordinary methods, while the accuracy of the results 

 are quite within the limits of error for all practical 

 purposes. There is no doubt that when the instrument 

 is better known, and its labour-saving property recog- 

 nised, it will be more commonly seen in the laboratory 

 and workshop than it is now. So many manipulations 

 can be done with it that, without some guide, its full value 

 cannot be appreciated. In the present little manual 

 the author brings these all together, and in such a form 

 that the reader can, by paying attention to the mechanical 

 and mathematical principles, obtain an intelligent interest 

 in the manipulations, and have confidence in the results. 



W. J. L. 



/ Fondainenii Matematici per la Critica dei Risullali 

 Speriiitenlali. Del Prof. P. Pizzetti. (Genova, 1892.) 



An elaborate memoir, of the nature of a complete treatise 

 on the Method of Least Squares, in its application to the 

 reduction to order of a long-continued series of experi- 

 ments and of their numerical results. 



It contains a valuable bibliography of writings on the 

 subject, arranged alphabetically according to authors' 

 names. 



Hitherto the astronomer has made most use of this 

 theory ; but the artillerist is now finding it important for 

 his purposes, in calculating from the number of hits to 

 effect a desired amount of destruction the amount of 

 ammunition required. G. 



Teppich-crzeuffung tin Orient. By various Contributors 

 Pp. 204. (W'len : K. K. Osterr.Handels-Museum, 

 1895.) 



Thls work consists of a series of monographs on im- 

 portant antique tapestries contained in European 

 museums and private collections, contributed by Sir 

 George liirdwood, Mr. C. Purdon-Clarke, .Mr. Vincent J. 

 Robinson, Mr. S. J. A. Churchill, Dr. W. Bode, M. 

 Gerspach, and M. O. M. Stoeckel. In addition to the 

 history of antique tapestries, the work contains descrip- 

 tions of a number of the more important types of modern 

 tapestries of the Levant, Persia, and India. The illustra- 

 tions are numerous and of high quality. 



A Laboratory Manual. By \V. R. Orndorff, A.B., Ph.D. 

 (Boston : D. C. Heath. London : Isbisier and Co., 

 1894., 



A COURSI': of experiments in organic chemistry, system- 

 atically arranged as an adjunct to Prof. Ira Remsen's 

 work on the " Compounds of Carbon." As Dr. Orndorff 

 has had a large experience in the laboratory work to 

 which the book refers, the conditions of the experiments 

 described can be depended upon, which is the highest re- 

 commendation that can be given to a manual of this kind. 



NO. r -^08, VOL. 5 1] 



LETTERS TO THE EDITOR. 



The Editor docs not hold himself responsible for opinions ex- 

 tressed by his correspondents. Neither can he undertake 

 to return, or to correspond zvilh the writers oj, rejectee 

 manuscripts intended for this or any other part o/ifATVRK. 

 No notice is taken of anonymous communications. ] 



Finger-Prints. 



I HAVE been quite unable, since I saw Mr. Faulds' letter in 

 your issue of October 4, to take the matter of it in hand hithet to ; 

 and I do so now only because I think Mr. P'aulds is entitled to 

 raise the question if he pleases. To the best of my knowledge, 

 Mr. Faulds' letter of 18S0 was, what he says it was, the first 

 notice in the public papers, in your columns, of the value of 

 finger-prints for the purpose of identification. His statement 

 that he came upon it independently in 1879 (? 1S78) commands 

 acceptance as a matter of course. At the same time I scarcely 

 think that such short experience as that justified his announcing 

 that the finger-furrows were " for-ever unchanging." 



How I chanced upon the thing myself in 1858, and followed it 

 up afterward?, has been very kindly slated on my authority by 

 ^Ir. Gallon, at whose disposal I gladly placed all my materials 

 on his request. Those published by him are only a part of what 

 were available. (See his "Finger-Prints," page 27, and his 

 " Blurred Finger-Prints.") To what is there stated I need now 

 only .add, at -Mr. Faulds' request, a copy of the demi-official 

 letter which I addressed in 1877 to the then Inspector-General 

 of Jails in Bengal. That the reply I received appeared to me 

 altogether discouraging was simply the result of my very 

 depressed state of health at the time. The position into which 

 the subject has now been lifted is therefore wholly due to Mr. 

 Gallon through his large development of the study, and his 

 exquisite and costly methods of demonstrating in print the many 

 new and important conclusions he has reached. 



I take the opportunity, in reference to a late article on An- 

 thropometry (in the A'ineteeiith Century of September 1894, 

 p. 365), to deprecate, as being to the best of my knowledge 

 wholly unproved, the assertion that the use of finger-marks m 

 this way was "originally invented by the Chinese." I have 

 met no evidence which goes anywhere near substantiating this. 

 As a matter of fact, I exhibited ihe system to many passengers 

 and officers of the P. and O. steamship Moii^'olia in the Indian 

 Ocean, during her outward voyage in February 1S77 ; and I 

 have the finger-prints of her captain, and of all those persons, 

 with their names. It is likely enough that the idea, which 

 caught on rapidly among the passengers, may have found a 

 settlement in some Chinese pott by this route, and have there 

 taken a practical form ; but whether that be so or not, I must 

 protest against the vague claim made on behalf of the Chinese, 

 until satisfactory evidence of antiquity is produced. 



Littlemore, November 7. \V. J. Herschel. 



(Trie Copy of Office Corv. ) 



Hooghly, Au^ist 15, 1877. 



Mv De.ar B . — I enclose a paper which looks unusual, 



but which I hope has some value. It exhibits a method of 

 identification of persons, which, with ordinary care in execution, 

 and with judicial care in the scrutiny, is, I can now say, for all 

 practical purposes far more infallible than photography. It 

 consists in taking a seal-like impression, in common seal ink, of 

 the markings on the skin of the two forefingers of the right 

 hand (these two being taken for convenience only). 



I am able to say that these marks do not ( bar accidents) 

 change in the course often or fifteen years so much as to affect 

 the utility of the test. 



The process of taking the impression is hardly more difticult 

 than that of making a fair stamp of an office seal. I have been 

 trying it in the Jail and in Ihe Registering Office and among 

 pensioners here for some months past. I have purposely taken 

 no particular pains in explaining the process, beyond once 

 showing how it is done, and once or twice visiting the office, in- 

 specting the signatures, and asking the omlah ' to be a little 

 more careful. The articles necessary are such as the a'a/Zari- 

 can prepare on a mere verbal explanation. 



Every person who now registers a document at Hooghly has 

 to sign his "sign-manual." None has offered the smallest ob- 

 jection, and I believe that the practice, if generally adopted, 

 will put an end to all attempts at personation. 



' Clerks. 2 Man in charge of stattODcr)'. 



