276 



NATURE 



[April 28, 192 1 



many months there are in the year does not 

 exist, and in some cases the reckoning by moons 

 is not even extended to the whole year. There is 

 a time when nothing particular happens and 

 nobody takes the trouble to observe or name 

 the moons ; such a period is, for instance, 

 the depth of winter in the far north. It is next 

 realised that the succession of seasons is inti- 

 mately connected with the motion of the sun. In 

 northern countries it is noticed by people having 

 a fixed dwelling-place that as midsummer is draw- 

 ing near the sun is rising further and further 

 north until a limit is reached. In this way the 

 date of the summer solstice, and similarly that of 

 the winter solstice, are determined, and a rough 

 idea of the length of the year is obtained, and is 

 improved by observing the heliacal risings of 



certain stars. It is thus found that the year is 

 longer than twelve moons, and shorter than 

 thirteen, and the next problem is how to make the 

 lunar months fit into the solar year by the occa- 

 sional interpolation or omission of a month. This 

 is the beginning of scientific chronology as we 

 see it arise and developed among the Babylonians 

 and the Greeks, 



Prof. Nilsson's valuable work was written 

 by him in Swedish, and translated into English 

 by a colleague in the University of Lund. . The 

 translator has followed the original closely, 

 sometimes too closely, and he uses some 

 curious expressions, such as "the phases of the 

 stars," or the "shifting year" of the Egyptians 

 (meaning their vague year). But these are trifling 

 faults in an otherwise excellent book. 



Obituary. 



Prof. A. W. Reixold, F.R.S. 



ARNOLD WILLIAM REINOLD, who died on 

 April II, was born at Hull on June 19, 1843, 

 and was the son of John Henry Arnold Reinold, a 

 shipbroker at that place. He was educated at 

 St. Peter's School, York, and matriculated at 

 Brasenose College, Oxford, in 1863, as an open 

 Somerset scholar. He had a distinguished career 

 as a mathematician, obtaining the University 

 junior and senior mathematical scholarships, first 

 classes in mathematics, moderations, and finals, 

 and in the School of Natural Science. In 1866 

 he was elected to a fellowship at Merton, and in 

 1869 became Lee's reader in physics and a senior 

 student at Christ Church. H3 was the late Prof. 

 Clifton's first demonstrator in the Clarendon 

 Laboratory, being succeeded by A. W. Riicker. 



In 1873 Reinold was appointed professor of 

 physics at the Royal Naval College, Greenwich. 

 His life-work was done here, as he held the 

 post for thirty-five years, retiring in 1908 on 

 reaching the age limit, and being rfiade a C.B. in 

 191 1. This professorship was a new appointment, 

 so that a laboratory and courses of physics had 

 to be organised; the laboratory buildings were 

 part of the sick quarters of the old hospital, and 

 finally occupied a considerable amount of space. 

 Besides our own naval officers, gunnery and tor- 

 pedo lieutenants, naval architects and engineers, 

 etc., there were occasionally foreign students 

 working here, and Reinold received a medal 

 from the Emperor of China in recognition of 

 work with Chinese students. It was at Green- 

 wich that he collaborated with Riicker in a series 

 of investigations on the properties of liquid films, 

 the first paper appearing in the Proc. Roy. Soc. 

 for 1877, and the final one in the Phil. Trans, 

 for 1893, with several between. He was a lec- 

 turer at Guy's Hospital for most of his time at 

 Greenwich, and a joint editor for several editions 

 of Ganot's "Physics." 



Reinold was signally devoid of any hobbies, 

 and seemed to have no recreations. His interests 

 NO. 2687, VOL. 107] 



apart from his work were mainly in the Physical 

 Society, of which he was an original member, if 

 not one of the founders, acting as secretary from 

 the beginning until 1888, when he became presi- 

 dent for two years; and in the Royal Society, of 

 which he became a fellow in 1883, and on the 

 council of which he served for some years. He was 

 a sensitive man with a charming manner, and was 

 liked by all who came in contact with him, being 

 always courteous and gentlemanly in the fullest 

 sense. Reinold retained his activities, mental and 

 otherwise, to the end, which occurred very sud- 

 denly ; he had just undertaken to write an obituary 

 notice for the Royal Society of his old chief, Prof. 

 Clifton. Married about 1866 to Miss Marian 

 Studdy Owen, he leaves a family of one daughter 

 and three sons. W. N. S. 



Robert Allen Rolfe. 



Systematic botanists, and especially orchid- 

 ologists, have sustained a grievous loss by the 

 death on April 13, after rather more than three 

 months' illness, of Mr. R, A. Rolfe, who, for 

 upwards of forty years, was an assistant in the 

 Herbarium of the Royal Botanic Gardens, Kew. 

 Mr. Rolfe was born at Ruddington, near Notting- 

 ham, on May 12, 1855. He joined the Kew 

 Herbarium staff in 1880, as a result of a public 

 competitive examination, having previously 

 gained some experience among cultivated plants 

 in the famous gardens at Welbeck Abbey, Notts, 

 and at Kew. It was anticipated that he would 

 retire from service next month, and a visit to 

 Central America was projected, for which a grant 

 in aid had actually been voted by the Government 

 Grant Board of the Royal Society. 



Mr. Rolfe 's contributions to botanical literature 

 have been numerous and important. For many 

 years past he was the generally accepted authority 

 in this country on the Orchidaceae ; it might truth- 

 fully be said that his reputation was world-wide. 

 He founded the Orchid Review in 1893, and edited 

 and wrote to a large extent the twenty-eight 



