U4 



information peculiarly suited to their purpose which he 

 alone of all men living possessed, and which he was 

 particularly anxious to communicate to others. 



About this time too, Sir E. Sabine resigned his office 

 of magnetical superintendent, and it might naturally have 

 been "supposed that Mr. Broun was the very man to 

 succeed him. The office was, however, discontinued. 

 He now made application to the Government Fund of 

 the Royal Society for a sum of money to enable him to 

 improve and complete the reduction of the Colonial 

 magnetic observations. But the immediate and apparent 

 responsibility from quarter to quarter of the possessor of 

 such grants, was peculiarly fatal to a man like Broun. 

 The work seemed to go on growing the more he examined 

 it, and he was never satisfied without going still more 

 deeply into the subject than he had already gone. 



Then his health began to give way, and the thought 

 that he had received money for which he had rendered 

 no equivalent hastened still more the progress of his 

 malady. 



At last the end came, and we can now hope no longer 

 to complete his labours as he would have himself com- 

 pleted them had he been spared to us but a little longer. 



It has been said of an eminent experimentalist that 

 great as were his successes, his failures must have cost 

 him even more thought. If this be true in experimental 

 research, it is peculiarly true in observational inquiry 

 where every idea in order to be tested entails a laborious 

 investigation. Mr. Broun, whose mind was very fertile, 

 must have often spent great labour apparently to no 

 purpose, but on the other hand his successes were very 

 marked, and he did not hesitate to consider a new fact 

 as abundant compensation for a large amount of failure. 

 We cannot attempt to give here an exhaustive catalogue 

 of his various labours. But we may allude to the volumes 

 embracing the results of the Makerstoun observations as 

 pre-eminent for the skill employed in the development of 

 new methods. These volumes alone must have cost him 

 an immense amount of thought. 



In 1861 he communicated to the Royal Society of 

 Edinburgh, two papers of marked value. In one of these 

 the errors and corrections of the bifilar magnetometer were 

 discussed, including the determination of its temperature 

 coefficient, which Mr. Broun showed might be found in a 

 more correct method than that hitherto adopted. 



The second of these papers was on the horizontal force 

 of the earth's magnetism, for which he established the 

 annual laws from a discussion of observations taken at 

 various places. He likewise discovered that the variations 

 of this element from day to day are nearly the same over 

 all the world. 



For these discoveries he was awarded the Keith Medal 

 of the Royal Society of Edinburgh. We have already 

 alluded to the great labour he spent upon the first volume 

 of the "Results of the Trevandrum Observations." In 

 this volume conclusions of the greatest scientific interest 

 are deduced, and Mr. Broun has been able to give in a 

 complete form the laws which regulate the solar-diurnal 

 variation of magnetic declination near the equator. But 

 his researches regarding the lunar-diurnal variation of this 

 elementform perhaps the most original and interesting part 

 of the volume. He has claims to be considered as an inde- 

 pendent discoverer of this variation, and he has certainly 

 increased our knowledge of its laws more than any other 

 magnetician. We may mention his observation that the 

 lunar action was reversed at sunrise and that it was 

 much greater during the day than during the night, 

 whether the moon was above or below the horizon, as 

 particularly noteworthy and likely to throw much light 

 on the theory of the subject. We have already alluded 

 to Mr. Broun's discovery of the similarity, all the world 

 over, of the changes from day to day of the earth's 

 horizontal force. Certain of these changes he found to 

 be due to the moon, while others had a period of 



NATURE [Dec. 4, 1879 



twenty-six days. These last he attributed to solar action, 

 and in discussing the subject he found that the greater 

 magnetic disturbances were apparently due to actions 

 proceeding from particular meridians of the sun. This 

 is a subject of very great importance, and its exact 

 meaning has yet to be discovered. 



Mr. Broun was no less eminent as a meterologist than 

 as a magnetician. His observations regarding the baro- 

 meter are of the greatest importance. In this branch of 

 inquiry he has shown the apparent simultaneity of the 

 changes of mean barometric pressure over a great part of 

 the globe, and he has likewise discovered a period of twenty- 

 six days. He was the first to commence those syste- 

 matic observations of clouds at various altitudes that are 

 now so extensively made, and in a paper read not long 

 since before the Royal Society of London, of which body 

 he was an old member, he pointed out certain relations 

 between atmospheric motions and the directions of the lines 

 of equal barometric pressure. For his various researches, 

 he obtained in 1878, just one year before his death, 

 the Royal Medal of that Society. 



These are only a few'of the many labours of one whose 

 loss, so deeply felt by all his friends, may be regarded 

 as a calamity by the cultivators of meteorology and 

 magnetism, branches of knowledge in which he was 

 second to none who has yet appeared. 



Balfour Stewart 



NOTES 



Dr. Warren de la Rue, F.R.S., has just sent to the 

 Chemical Society Research Fund a third donation of 100/., the 

 whole amount to be devoted to a single research. 



In the person of Lady Sabine, who ;died at Ashley Place on 

 the 28th ult., at the age of seventy-two years, a woman of most 

 remarkable clearness of intellect and of power of memory has 

 passed away. In 1827 she married Sir Edward (then Captain) 

 Sabine, and for more than fifty years her main occupation and 

 her chief enjoyment was to assist him in his investigations, espe- 

 cially in terrestrial magnetism. None but her most intimate 

 friends can know how much of the laborious calculations in the 

 " Contributions " were really effected by her, while she translated 

 Humboldt's " Cosmos " and "Ansichten der Natur," besides 

 numerous smaller papers. One of their oldest friends has truly 

 said, " I deeply sympathise with Sir Edward; the death of his 

 wife has rendered the number of beautiful lives in the world one 

 less." 



The following are the probable arrangements for the Friday 

 evening meetings before Easter, 1880, at the Royal Institution :— 

 lanuary 16, Prof. Dewar, F.R.S. ; January 23, Dr. W. B. 

 Carpenter, C.B., F.R.S. , "Sea and Land in Relation to Geo- 

 logical Time;" lanuary 30, John Marshall, F.R.S., "Propor- 

 tions of the Human Figure ; " February 6, William Huggins, 

 D.C.L., F.R.S. ; February 13, W. H. Preece, C.E., "Wheat- 

 stone's Telegraphic Achievements ; " February 20, Rev. H. R. 

 Haweis, " Old Violins ; " February 27. Frederick J. Bramwell, 

 FRS. ; March 5, II. N. Moseley, F.R.S., "Deep-Sea 

 Dredging and Life in the Deep Sea;" March 12, C. William 

 Siemens, D.C.L., F.R.S. ; March 19, Trof. Tyndall, D.C.L., 

 F R.S. The following are the lecture arrangements before 

 Easter :— Christmas Lectures (adapted to a juvenile auditory) : 

 Prof Tyrdall, D.C.L., F.R.S., six lectures on" Water and Air, 

 on December 27 (Saturday), 30, 1879, January I, 3. 6, 8, 

 1SS0; Prof. Edward A. Schafer, F.R.S., ten lectures on I he 

 Physiology of Muscle," on Tuesdays, January 13 to March 16 ; 

 H. Heathcote Statham, two lectures on " Modern Architecture 

 since the Renaissance," on Thursdays, January 15 and 22 ; Trot. 

 Dewar F R.S., eight lectures on "Recent Chemical Progress, 

 on Thursdays, January 29 to March iS ; Prof. T. Rupert Jones, 



