June i8, 1896J 



NA TURE 



165 



matical works. Mr. Uixon was Senior Wrangler in iSS6, and 

 is Professor of Mathematics at Clahvay. 



A lectureship in Hausa is about to he founded, in virtue of a 

 benefaction by the Hausa Association. The language ranks 

 with Arabic and Suaheli as one of the most important West 

 African tongues used within the British sphere of influence. 



The (General Board propose that a Professorship of Mental 

 Philosophy and Logic, with a stipend of /,"7oo a year, should be 

 forthwith established. Prof. Sidgwick has generously offered 

 to accept a diminished stipend of ^^500 a year for the next six 

 years in order that funds may be available for this purpose. 



The Tyson Medal for Astronomy has been awaided to Mr. 

 E. T. Whitaker, of Trinity. 



Mr. \V. Mather has received the thanks of the University for 

 a valuable gift to the Engineering Laboratory of an experimental 

 steam-engine and dynamo. 



.\ Latin letter o( congratulation to Lord Kelvin on the jubilee 

 of his Professorship at Glasgow was approved at the Congrega- 

 tion on June 1 1, and was ordered to be sealed with the Common 

 Seal of the University and presented to him by the University 

 delegates to Glasgow. 



The Syn<licate on Women's degrees was appointed without 

 opposition, and have already held their first meeting. Their 

 report will not be issued until next Term. 



The following appointments have been made in the 

 Northern Polytechnic Institute, Ilolloway : — Mr. Hubert 

 .\. (iarratt. Senior Lecturer in Engineering, University 

 College, Bristol, to be Head of the Engineering Department ; 

 Mr. V. A. .Mundella, Assistant Lecturer in Physics and 

 Electrical Engineering, Durham College of .Science, Newcastle, 

 to be Head of the Physics and Electrical Engineering Depart- 

 ment : Dr. Thomas Ewan, Assistant Lecturer in Chemistry, 

 the Yorkshire College, Leeds, to be Chief Assistant in the 

 Chemical Department. Other recent appointments are : — Dr. G. 

 Krege to be Professor of Mathematics at Jena ; Dr. Lickfett to 

 be Director of the Hygienic-bacteriological Institute at Danzig ; 

 Dr. Scholl to be Extraordinary Professor of Chemistry in the 

 Technical High School at Karlsruhe. Mr. E. A. tlardner, 

 formerly Director of the British School at .\thens, to be Vates 

 Professor of .Arch.-eology in University College, London ; Dr. 

 Paul Eisler to be Extraordinary Professor of Anatomy at Halle ; 

 Dr. L. Joubin to be Professor of Zoology, and Dr. H. Prous to 

 be Extraordinary Professor in Lille University ; Dr. Theobald 

 Smith to be Professor of Comparative Pathology in Harvard 

 University. 



The Technical Instruction Committee of the North Riding 

 County Council some time ago substituted a system of individual 

 instruction in cheese and butter making at the farm-house of 

 any farmer who desired it, for the more commonly adopted 

 travelling dairy- school. In addition to this method of instruction 

 they have agreed to a scheme whereby a jiermanent dairy school 

 will be opened at Helmsley in the course of the present month. 

 The school is being built by the Earl of Feversham, and is to be 

 placed at the Committee's disposal, who are rnaking themselves 

 responsible for the proper fittings and apparatus. It is con- 

 fidently anticipated that the school, which will be .styled the 

 " Ryedale Dairy School," will be much used and greatly 

 appreciated. 



On Thursday evening last it was resolved by 332 votes to 83, 

 that boroughs of not less than 20,cxx) population should form 

 separate educational authorities. This will mean, as the Vice- 

 President of the Council pointed out in his speech on this 

 amendment, that in addition to the 128 authorities which there 

 would have been as the Bill originally stood, we are to have 241 

 more authorities added, that is, provided the amendment passes 

 the House of Lords, p'urther, since there is no doubt populous 

 urban districts will claim to be treated like municipal boroughs, 

 and it seems only reasonable to suppose that such will be granted 

 similar powers, forty-nine more authorities will be brought in, 

 making a total of 418 separate centres for the Education Depart- 

 ment to deal with. In some cases the result will be extraordinary ; 

 for example, in Lancashire there will be some forty-two 

 different educational authorities. The extent to which the work 

 of the County Councils would suffer should this concession of 

 the Government become law, can only be appreciated by those 

 who know the spirit in which small local authorities approach 

 any matters pertaining to .secondary education. 



NO. 1390, VOL. 54 J 



SOCIETIES AND ACADEMIES. 

 London. 

 Physical Society, June 12. — Captain Abney, F.R.S., Presi- 

 dent, in the chair. — Mr. Campbell read a paper on the measure- 

 ment of very large and of very small alternating currents. 

 The author advocates the use of air-coil transformers for 

 measuring voltages and currents which are either above or 

 below the range of the instruments available. If an 

 attempt is made to measure the current in the primary 

 of an aircoil transformer by observing the voltage on an open 

 circuit secondary, it is found that the readings depend on the 

 frequency. In order to overcome this difficulty the author uses 

 a closed secondary with a very high inductance. In this case 

 the primary current is proportional to the secondary current, 

 which latter may be measured by an ammeter. The author has 

 also investigated the case of transformers with iron cores, and ot 

 which the inductance of the secondary is large. In the case ol 

 a ring transformer with a closed magnetic circuit, if the load on 

 the secondary consisted solely of a Kelvin loo-ampere balance 

 of very low resistance, the ratio between the priinary and 

 secondary currents is practically con.stant. With an open 

 magnetic circuit transformer, however, this is not found 

 to be so, as the ratio between the primary and secondary 

 current varies considerably with the frequency. Mr. 

 Blakesley said that the author's arrangement could only be used 

 for measuring the current in the primary. He (Mr. Blakesley). 

 had shown how to measure alternating currents by means of 

 dynamometers, and without the necessity for any speciaL 

 apparatus. Mr. Griffiths exhibited and described his improved 

 form of resistance box. This resistance box has many novef' 

 features : (l) It permits of all the coils being compared with 

 one another, without the use of standard coils, and with great 

 ease and rapidity. Hence it is sufficient at any time to 

 compare any one of the coils with a standard to obtain 

 the correction to be applied to all the coils. (2) The 

 bridge wire can be calibrated by means of the box itself. (3) 

 The temperature of the coils can be accurately determined, 

 since they consist of bare platinum-silver wire wound on mica 

 and immersed in an oil bath, which bath is kept stirred. (4) 

 The resistance of the leads from the box to the object being 

 tested is eliminated, as well as any error due to a change 

 in this resistance with temperature. (5) The coils are 

 arranged according to a binary scale, and the author 

 claims that it is possible to measure resistances up to 

 105 ohms, to within O'oooooi ohm. (6) All the coils, after 

 being adjusted, have been heated to redness and allowed to cool 

 slowly, so that all strain has been removed from the wire. (7) 

 By having a separate pair of blocks for each plug, it is 

 impo.ssible for the insertion of one plug to affect the 

 fit of a neighbouring plug. The plugs themselves are so made 

 that no part of the plug is wider than the top of the hole, and so 

 it is impossible to wear a " .shoulder " on the plug. Prof. A 

 Gray said that Mr. Grifiilhs had discovered and remedied all 

 the weak points of the ordinary form of bridge. Lord Kelvin 

 had ordered the parafiSn to be melted off the coils of one of his 

 resistance boxes, and it was found that the resistance of the 

 coils altered considerably, owing, no doubt, to the strain to 

 which the wire had been subjected, when imbedded in the solid-, 

 paraffin. Lord Kelvin had made coils without paraffin, and 

 was specially in favour of the use of the binary scale. Prof. 

 S. P. Thompson said he considered the binary scale the weak, 

 point of the author's arrangement, since it did not permit of 

 ratios other than I to I being employed. Mr. Campbell 

 asked what current could safely be passed through the coils. 

 The author in his reply said that he believed it to be a great 

 mistake to employ any ratio for the arms other than i to i, 

 — Prof. S. P. Thompson read a communication on Rontgen rays. 

 The author, after describing the various forms of tubes he had 

 made with a view of discovering the best form for the production 

 of Rontgen rays, gave an account of the experiments he had 

 made to try and obtain some indication of polarisation. In thi.s 

 connection a large number of crystals have been tested, but the 

 experiments have all given negative results. The author 

 exhibited an electroscope with aluminium leaves and enclosed in 

 a wire-gauze screen, to protect it from the influence of outside 

 electric changes, by means of which he was able to show the 

 discharge of a positively or negatively electrified body by 

 means of the X-rays. A method of obtaining dust figures 

 by the discharge of an electrified body by the X-ray.s 



