9 8 



NA TURE 



[May 31, 1888 



the latter began to feel the approach of old age, and the pro- 

 spect of a speedy termination of this important undertaking 

 became more and more doubtful, when, in the year 1872, a 

 young German scholar, Dr. Sachau, boldly stepped into the 

 breach, and promised to devote all his time to this great 

 enterprise. After fifteen years of hard work he has redeemed 

 his pledge. He has given us the Arabic text of Al-Biruni, 

 and he is now engaged in printing an English translation 

 of it. We doubt whether anyone could have been found 

 so well qualified for the task. Dr. Sachau has long been 

 known as a hard-working, honest, and thoroughly sound 

 scholar. He stands in the first rank among the students of 

 Arabic and Persian, and he possesses, at the same time, a 

 fair knowledge of Sanskrit. He is now one of the brightest 

 stars in the Univerity of Berlin, and has lately been ap- 

 pointed there as Director of the newly-founded Imperial 

 School of Oriental Languages. He was well prepared for 

 his task by having previously published another work of 

 Al-Biruni's, the text and English translation of " The 

 Chronology of Ancient Oriental Nations." Few people 

 can appreciate the enormous difficulties of publishing for 

 the first time an Oriental text like that of Al-Biruni. Dr. 

 Sachau was, no doubt, more fortunate than his predeces- 

 sors in securing a manuscript of Al-Biruni's, belonging 

 to M. Schefer, which professes to have been copied from 

 a copy in the handwriting of the author. But even thus 

 the labour of editing and translating such a text, which 

 had never been edited and translated before, was enor- 

 mous. When speaking of the difficulties which he had 

 to overcome in editing Al-Biruni's chronological work, 

 Dr. Sachau writes : " I have boldly attacked the some- 

 times rather enigmatic style of the author, and if I have 

 missed the mark, if the bewildering variety and multi- 

 plicity of the subject-matter have prevented my reaching 

 the very bottom of every question, I must do what more 

 or less every Oriental author does at the end of his work 

 —humbly ask the gentle reader to pardon my error and 

 correct it." There is the true ring of the bond fide scholar 

 in this. No one is nowadays considered a real Oriental 

 scholar who has not won his spurs by an editio princeps. 

 After a text has once been constituted by a comparison of 

 manuscripts more or less faulty ; after a translation has 

 once been accomplished, however imperfect, it is easy 

 enough to print a new so-called critical edition, or a new 

 so-called improved translation. But the scholars who take 

 the first, and the scholars who take the second, step 

 belong to different races. They differ as Columbus who 

 discovered America differs from the traveller who now 

 crosses the Atlantic in seven days. " Generations of 

 scholars," as Dr. Sachau says, "have toiled to .carry the 

 understanding of Herodotus to that point where it now 

 is, and how much is wanting still ! " To expect, there- 

 fore, that Al-Biruni's text, as edited here for the first time, 

 or its translation, should be free from mistakes would 

 only show a complete ignorance of the conditions under 

 which Oriental scholars have to work. There may be 

 hereafter better editions of Al-Biruni ; there never can 

 be one so creditable to its author as this editio princeps. 

 We could have wished that a work of such importance 

 to students of Indian history had been carried out by an 

 English scholar. But, failing that, we have at least the 

 satisfaction that the expense of publishing the Arabic 

 original of the " Indica " has been generously defrayed 



by the Indian Government, following in this respect the 

 noble example set by the patron of Al-Biruni himself, the 

 powerful Sultan Mahmud of Ghazna. 



THE SCIENTIFIC WRITINGS OF JOSEPH 

 HENRY. 



The Scientific Writings of Joseph Henry. Two Vols. 

 8vo, pp. 1082. (Washington : Smithsonian Institution, 

 1886.) 



UNDER the above title, two handsome volumes have 

 recently been published by the Smithsonian Insti- 

 tution, Washington, containing the papers published by 

 its late distinguished Secretary in various scientific serials 

 through the long period of fifty-four years. It is character- 

 istic of the man that, although for thirty-two of those years 

 he had almost unrestricted command of the publishing 

 resources of that great institution, not one of his papers was 

 given to the world through the medium of the " Smith- 

 sonian Contributions" or "Miscellaneous Collections," 

 or in any way at the expense of its funds. They range 

 over a great variety of subjects, chiefly in electrical 

 physics and meteorology, and in date from 1824 to 1878. 



As may be inferred from the earlier of these dates, 

 when Faraday was still an assistant to Sir Humphry 

 Davy, in the laboratory of the Royal Institution, and 

 Henry a private tutor in a family at Albany, New York, 

 many of these papers are reprinted for their historical 

 interest rather than for their present scientific value ; but 

 his fellow-countrymen, in acknowledging Faraday's pre- 

 eminence, delight to point out in how many particulars 

 Henry walked pari passu with him in the then nearly 

 untrodden paths of electro-magnetism, under immense 

 relative disadvantages. As early as 1835, Henry, then a 

 Professor at Princeton, New Jersey, connected his resid- 

 ence with his laboratory in the Philosophic Hall by a 

 telegraph, in which the galvanic circuit was completed 

 through the earth — probably the first realization of that 

 familiar property on which all our telegraph circuits are 

 now dependent. It was a little later (in 1842) that he 

 showed the writer of this short notice, under promise of 

 secrecy, an experiment which at the moment greatly in- 

 terested him. A long bar of iron was wrapped in a coil 

 or ribbon of copper, half an inch wide ; two copper wires, 

 each terminating in a small ball, were soldered to the 

 bar. On holding these balls to the ears, and transmitting 

 a strong current through the coil, a very distinct musical 

 note was heard each time the current was made or broken 

 He narrowly missed forestalling Faraday in the gre 

 discovery of producing electric currents by the rotati 

 of an electro-magnet or movement of its armatur 

 Henry caused an electro-magnet of unusual power to 

 constructed in August 1 831, with a view to realizing hi 

 conceptions on this subject. He was at the time accident- 

 ally interrupted in pursuing his experiments, and did not 

 resume them until May or June 1832 ; and in the mean- 

 time (in February 1832) Faraday had made his inde- 

 pendent discovery. 1 As early as 1843, Henry proposed "a 

 new method of applying the instantaneous transmission 

 of an electrical action to determine the time of tlv 

 passage of a (cannon) ball between two screens, plac 



1 Philosophical Magazine, April 1832. 



211. 



I 



