May 



1903] 



NATURE 



93 



A liEW SYNTHESIS OF INDIGO. 



A N important new synthesis of indigo is described by Dr. 

 T. Sandmeyer in the April number of the Zeitschrift 

 fiir Farben- uttd Textil-C hemic. The starting point for the 

 synthesis is thiocarbanilid, CS(NH.C8H,)j, which is con- 

 verted in one operation by the simultaneous action of white 

 lead and potassium cyanide into the hvdrocyanide, 

 C,H5.N:C(C\).NH.C,H5, of carbodiphenylim'ide. This 

 compound is changed by the action of yellow ammonium 

 sulphide into the thioamide, 



C,H,.N:C(CS.NH,).NH.C,H„ 



■which, when stirred into warm sulphuric acid, undergoes 

 condensation, and yields an a-isatinanilide, 



/NHv 



QH^^ 



\co- 



)C:NC8H5. 



The anilide is converted directly into indigo when dissolved 

 in alcohol and reduced with ammonium sulphide, but the 

 indigo separates in glistening crystals which cannot easily 

 be reduced by the ordinary methods, and so is unsuitable 

 for commercial use. A better method, and one which 

 renders it unnecessary to separate the isatinanilide from the 

 sulphuric acid used in its preparation, consists in allowing 

 the acid solution to flow into ice-water simultaneously with 

 a solution of sodium sulphide, when the anilide is converted 

 into thioisatin, 



qh/ >cs, 



■which is thrown down as a bulky precipitate. In order to 

 prepare the indigo it is now only necessary to make the 

 precipitate into a thin paste and mix it with a little alkali, 

 when the thioisatin rapidly decomposes into indigo and 

 sulphur. The sulphur is removed by extracting with carbon 

 disulphide, and the indigo is left in the form of light, dark- 

 blue blocks, which readily crumble when rubbed between 

 the fingers, and can be made into a uniform paste which 

 Is easily reduced to indigo-white. The patents are held 

 and are being worked by J. R. Geigny, of Basle, and the 

 process may prove to be a formidable rival not only to 

 natural indigo, but also to the synthetical process employed 

 bv the Badische Anilin- und Soda-Fabrik. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Oxford. — The 249th meeting of the Junior Scientific 

 Club was held on May 20. Mr. H. S. Souttar gave an 

 exhibit of an automatic method of drawing capillary tubes 

 intended for use in the capillary electrometer. Mr. S. A. 

 lonides read a paper on " Mining in Cornwall," in which 

 he gave an account of the methods employed for raising 

 and washing the tin ores. 



Cambridge. — Mr. Andrew Graham, who has for nearly 

 forty years held the office of chief assistant at the observ- 

 atory, and is known to astronomers as the discoverer of 

 Metis, is retiring at the age of eighty-eight. It is pro- 

 posed to assign him a pension of 200/. a year. 



The use of the Senate House has been granted to the 

 local committee of the British Association for the meeting 

 to be held in Cambridge next year. 



Lord Kelvin and Lord Lister are to receive the honorary 

 ■degrees of doctor of science from the University of Wales 

 next November. 



Mr. W. M. Childs, vice-principal of University College, 

 Reading, has been elected principal of the College in suc- 

 cession to Mr. H. J. Mackinder, who resigns office in 

 September next. 



It is stated by the Electrician that a donation of nearly 

 4o,oooZ. has been promised by Lord Iveagh to Trinity 

 College, Dublin, with the object of building and equipping 

 scientific laboratories. 



The Liverpool University Bill was, on Tuesday, reported 

 for third reading by Lord Morley, Chairman of Committees 



NO. 1752, VOL. 68] 



of the House of Lords. The object of the Bill is to separate 

 University College, Liverpool, from the Victoria University, 

 and to merge it into the University of Liverpool. 



The annual report of the Royal Agricultural Society, 

 which was adopted at the general meeting held on May 22, 

 states that with the view of bringing before the public the 

 general characteristics of the teaching now provided at 

 agricultural colleges, and of directing attention to the 

 Society's own share in this work as a national examining 

 body, the council has decided to organise an agricultural 

 education exhibition as a new feature of its annual show. 



In his recent paper read at a meeting of the Society of 

 Arts Mr. G. T, Morrison gave a clear and useful account 

 of the modern methods of construction of maps and charts. 

 His descriptions of orthographic, stereographic, Mercator's, 

 gnomonic and elliptical projections should prove of great 

 assistance to teachers who wish to explain the methods 

 employed to make maps, which either give good general 

 ideas of the appearance of the whole or of parts of the 

 earth, or retain some one property of the sphere at the 

 expense of disregarding the others. Mr. Morrison thinks 

 that for the purpose of teaching geography a projection 

 based, not on any distinct mathematical rule, but on a 

 system of compromise, is on the whole the best — one, for 

 example, on which the meridians and parallels are spaced 

 at equal distances throughout. 



Arrangements have been made for an allied colonial 

 universities dinner and conference to be held early in July. 

 The conference will be held on July 9 at the rooms of the 

 Royal Society, Burlington House (by permission of the 

 president), to discuss the question of the coordination of 

 university education throughout the King's dominions, and 

 the development of post-graduate courses in applied science. 

 It is expected that an Imperial council will be formed to 

 deal permanently with these interests. The dinner will be 

 held on Friday, July 10, at the Hotel Cecil. The Lord 

 Chancellor and other statesmen, many high public officials, 

 representatives of colleges and universities in the United 

 Kingdom and the colonies, and several distinguished men 

 of science are expected to be present. Graduates and under- 

 graduates of colonial universities wishing to attend the 

 dinner, or to take part in the conference, are requested 

 to write as soon as possible to Mr. C. Kinloch Cooke, hon. 

 sec, 3 Mount Street, London, W. 



The annual catalogue, 1902-3, of the Massachusetts 

 Institute of Technology at Boston gives very full particulars 

 of the numerous courses of instruction in connection with 

 the institute, a clear plan of the extensive buildings, a 

 register of graduates, and other interesting details. The 

 tuition fee for regular students is 50/. per annum, for half 

 a year or any shorter period the fee is 30/. Special 

 students pay, in general, the full fee ; but when a few 

 branches only are pursued and the time required for instruc- 

 tion is limited, applications for a reduction in the fees are 

 considered. Regular students whose financial necessities 

 are such as to prevent their continuance at the institute 

 are encouraged to apply for aid to the scholarship com- 

 mittee of the faculty. Students may conveniently live in 

 any of the nearer cities or towns, since the hours of the 

 institute are from 9 to 5. The cost of board and rooms in 

 Boston and the neighbouring towns need not exceed from 

 thirty shillings to two pounds a week. The cost of books 

 and material varies from five to seven pounds a year. 



The second clause of the London Education Bill, referring 

 to the constitution of the education committee was with- 

 drawn by the Government on Monday. In its original form 

 the Bill provided for the appointment of thirty-one repre- 

 sentatives of the borough councils upon the committee. 

 This number wa£ reduced to twelve in Committee of the 

 House of Commons last week, but the compromise pleased 

 nobody, so the whole clause, with its restrictions upon the 

 local authority with regard to the constitution of the Educa- 

 tion Committee, has been omitted from the Bill. By this 

 action the London County Council, so far as the constitu- 

 tion of its education committee is concerned, is placed in 

 precisely the same position as other local authorities 

 brought into being by the Act of last year. The Council 

 will frame a scheme for itself, just as other county councils 

 have done, or are doing, and under the same ' conditions. 



