December 29, 1898J 



NA TURE 



201 



latter limiting form, and not the former, which is the graph of 

 the sum of the Fourier's series. 



The matter here discussed is perhaps that referred to by 

 Prof. Michelson in N.vrURE of October 6, but I did not under- 

 stand his letter so. In regard to his present communication, I 

 agree with him if he means that it is just as necessary, in 

 tracing the part of the curve C„ near the vertical part of the 

 broken line, to take a particular value of n, as it is to keep x 

 within a narrow range of values corresponding to n. But this 

 admission is not equivalent to admitting that an infinite series 

 may be summed by stopping at any particular term. Rather it 

 confirms the conclusion, explained above, that the graph of the 

 sum of the infinite series contains no vertical line. 



December 22. A. E. H. Love. 



The Schmidt-Dickert Relief Model of the Moon. 



The present location of the Schmidt-Dickert relief model of 

 the moon is probably not generally known in Europe. Webb's 

 "Celestial Objects for Common Telescopes" (edition of 1896) 

 states that the model is in Bonn, and this impression probably 

 generally prevails. As a matter of fact the model has been for 

 about twenty years in America. It has been on exhibition only 

 at rare intervals during the time, however, and hence has been 

 lost sight of. By a disposition recently made of it, it has 

 fortunately become available to students of science and the 

 public generally. Through the generosity of Mr. Lewis Reese, 

 of Chicago, it has been presented to the Field Columbian 

 Museum, and is now installed in this institution. 



The model is in the form of a hemisphere about nineteen feet 

 in diameter, and upon its surface are shown, in proportional 

 relief, over 20,000 distinct localities. In his original descrip- 

 tion. Dr. Schmidt, the eminent selenographer, states that the 

 details were based on the chart of Beer and Madler, but many 

 features were added from his own observations. He also states 

 that he carefully guided and watched over the work of con- 

 struction, and with his own hand tested its correctness in all 

 essential particulars. These statements give sufficient assurance 

 of the accuracy of the model, and the confidence with which it 

 may be studied. It is probably the best substitute extant for a 

 trip to the moon. Oliver C. Fakrington. 



Field Columbian Museum, Chicago, December 12. 



Maxwell's Logic. 



In a paper on the experimental verification of Ohm's law (Brit. 

 Assoc. Report, 1876), Maxwell makes the following statement. 



"Assume that the resistance of a given conductor, at a given 

 temperature, is a function of the strength of the current. Since 

 the resistance of a conductor is the same for the same current, 

 in whichever direction the current flows, the expression for the 

 resistance can contain only even powers of the current." 



It seems to me that such an argument is not applicable to a 

 case of this kind. 



Consider, for example, the flow of a liquid along a capillary 

 tube. We might define the resistance of any portion A B of 

 such a tube to be the ratio of the diff'erence of pressure between 

 A and B to the quantity of liquid flowing across any section in 

 unit time. 



Now would it not be equally legitimate to apply the above 

 reasoning to this case, and prove that the resistance of a capillary 

 tube could not vary as the first power of the velocity ? Although 

 of course, there may be no physical analogy between flow of 

 liquid and electric current. Again, imagine a uniform wire 

 A B along which a current of electricity is flowing, the ends 

 A and B dipping into mercury cups (say). Now, instead of 

 reversing the direction of the current, let the wiie be turned end 

 for end. Surely there is no difference between this and the 

 previous case, and yet the current in the wire is reversed. 



John Lister. 



Royal College of Science, London, South Kensington, 

 S.W., December 12. 



LORD IVEAGH'S GIFT. 

 'T'HE announcement, made in the daily papers last 

 ■*■ week, of Lord Iveagh's intention to devote the 

 princely sum of 250,000/. to the endowment and pro 

 motion of bacteriological research in England, has 

 arrested the attention of the country and of every class 



NO. 1522, VOL. 59] 



of the community. The humane and enlightened senti- 

 ments that have actuated Lord Iveagh, and the liberal 

 manner in which these have been given effect, constitute 

 a unique claim to the gratitude and appreciation of his 

 fellow countrymen. 



The distinction of such gifts had hitherto remained, 

 and appeared likely to remain, the prerogative of 

 .'\merica and American millionaires. The open-handed 

 liberality of Rockfeller, Armour and many others has 

 enabled the United States to provide endowment for 

 research and to equip laboratories on a scale of com- 

 pleteness unattempted in the mother country, whilst on 

 the continent the scientific worker has long found 

 encouragement and support in State-aided institutions. 

 The result has been that in bacteriological as well as 

 other branches of inquiry England has lagged behind. 



Lord Iveagh's decision to devote the proposed en- 

 dowment to an Institute that had been endeavouring 

 with inadequate means to carry out the work with 

 which he sympathises, has met with widespread approval. 

 It is now seven years since the British Institute of 

 Preventive Medicine vvas founded with the view of 

 establishing in England a national home for bacterio- 

 logical work and inquiry. The scheme received its in- 

 ception at a meeting held at the Mansion House, and 

 from the first obtained the sympathy and support of 

 eminent men of science and members of the medical 

 profession. A fund was raised at the same time to 

 provide poor patients with the means of proceeding to 

 Paris to undergo the Pasteur treatment for rabies. This 

 fund is still administered by the Institute, and no year 

 has passed without several claims being made for its 

 help. 



The new Institute was duly incorporated under the 

 Companies Act, and a Council was appointed to further 

 its objects — first amongst these being investigations in 

 connection with the prevention and treatment of infectious 

 diseases. The Council elected represented all branches 

 of scientific work likely to be benefited by bacteriological 

 investigation, and the work of the Institute was thus at 

 the outset wisely placed on the broadest possible basis. 



The services of Lord Lister, as Chairman of Council, 

 and of Sir Henry E. Roscoe, as Hon. Treasurer, have 

 been of inestimable value to the fortunes of the Institute. 

 The liberality of the Grocers' Company and of private 

 individuals, along with a handsome donation from the 

 Trusteesof the late Mr. Berridge, enabled the Council to 

 take steps to acquire a building site. A favourable site' 

 was acquired on easy terms at Chelsea, through the 

 liberality of the Duke of Westminster, and building 

 operations were commenced. The amalgamation of the 

 College of State Medicine with the Institute was effected 

 at the same time, and in this way temporary premises 

 were acquired at Great Russell Street for the initiation 

 of work. The Institute occupied these premises during 

 four years, and the various departments to be established 

 at Chelsea were successfully organised through the 

 efforts of a small but zealous staff. The discovery by 

 Behring of the antidiphtheria serum, and its beneficial 

 use abroad, led the Institute to undertake its preparation, 

 for the first time in this country. A farm was rented at 

 Sudbury, near Harrow, and provided with laboratory 

 and stabling accommodation, and the preparation of the 

 serum commenced. A public appeal was made for 

 funds, and a sum of money, sufficient to pay the initial 

 e.\penses of the new- departure, was raised. The work of 

 the antitoxin department of the Institute has since then 

 greatly expanded — the antistreptococcus and antitetanus 

 serum being now prepared, as well as the diphtheria 

 serum, and placed at the disposal of medical men. The 

 Institute also undertook the preparation of tuberculirk 

 and mallein for diagnostic purposes. 



The work undertaken in the antitoxin and other de- 

 partments proved a serious drain on the resources of the 



