December 20, 1894] 



NA TURE 



179 



machine in the previous figures will show that the ex- 

 tremities of the wings have been differently constructed, 

 being composed at the ends of a series of feather-like 

 sails. These latter are connected with a small machine, 

 near the operator's body, which is driven by compressed 

 carbonic acid gas ; it is set in motion by a simple 

 pressure of the finger. Such an addition has of course 

 increased very considerably the weight and, therefore, 

 the difficulty of handling the apparatus, and as yet it has 

 only been used when the conditions were very suitable, 

 as one serious fall would break up the machine. 



Nevertheless the results up to now are very promising, 

 and in calm weather Herr Lilienthal has been able to 

 considerably prolong his flights. When, with the 

 ordinary sailing machine, he would have come naturally 

 down to the ground, he has found that an occasional 

 Happing of these wings has helped to sustain him a longer 

 lime in the air, and to consequently cover greater 

 distances. 



Herr Lilienthal has shown now, that, with the simple 

 sailing machine, flights can be made without any great 

 risk. It would be good for the future progress of this 

 mode of sailing if those interested in it, and who have 

 the time and money, would take it up and pursue it 

 further. What is wanted now is experience, and this 

 can only be obtained by the co-operation of many 

 workers. 



PE TERS-DENZA—RANYARD . 



A STRONG. MI CAL science has lost three of its 

 ■'*■ votaries during the present month. Dr. C. F. W. 

 Peters died on December 2, and Father F. Denza, as 

 well as Mr. A. C. Ranyard, passed away on Friday last. 

 Dr. Carl Friedrich Wilhelm Peters, Director of the 

 Konigsberg Observatory, died on December 2, after a 

 protracted illness. He was born on April 16, 1S44, at 

 the Pulkowa Observatory, where his father. Prof. C. A. 

 F. Peters, held an appointment under the Russian 

 Government. In 1849 his father was appointed 

 to the Chair of Astronomy at Kunigsberg, and 

 in 1S54 he was made Director of the Altona 

 Observatory, which was afterwards transferred to Kiel. 

 The son studied astronomy and mathematics at Berlin, 

 Kiel, .Munchen, and Goitmgen, and was placed on the 

 staff of the Hamburg and Altona Observatories. Between 

 1S69 and 1S72 he made some valuable pendulum obser- 

 vations, chiefly for the Prussian Government. As 

 Privatdocent at Kiel University he undertook a long 

 series of chronometer tests for the German Navy, in the 

 course of which he proved that they are influenced by 

 changes of humidity as well as by changes of tempera- 

 ture. In iSSo, upon the death of his father, he edited 

 the Aslronomisc/ic Nachrichten for a year, after which 

 he was appointed Extraordinary Professor at Kiel 

 University. In 1SS3 he undertook the direction of the 

 Naval Chronoinetric Observatory at Kiel, whence he 

 proceeded in 1S8S to the directorship at Kunigsberg, 

 where he terminated a useful and laborious career. 



Father F. Denza died at Rome on the 14th inst. 

 from cerebral hemorrhage. He was well known to 

 the scientific world by his works in astronomy, 

 meteorology, and terrestrial magnetism, and at the 

 time of his death was President of the Italian 

 Meteorological Society, and Director of the Observatory 

 at Moncalieri, which he founded in 1859, as well as of 

 the \atican Observatory, which was established by the 

 Pope in 1S91. It was owing to the untiring energy of 

 Father Denza that the ConispoiukiKa Mctcorologica 

 Jliiliana was established in connection with the .Mpme 

 Clubs, and that the results of observations at a large 

 number of stations in the Alps and Apennines have been 

 regularly published in the organ of the Italian .Meteoro- 



NO. 1312, VOL. 51] 



logical Society. He was elected an honorary member of 

 the Royal Meteorological Society in 1870. 



In astronomy his chief work relates to the observation 

 of meteors. For several years he issued instructions to 

 observers of meteors previous to every important shower, 

 and he published numerous tables and papers on the ob- 

 servations carried on under his guidance, both in Comptcs- 

 rendtis and the Monthly Notices of the Royal Astro- 

 nomical Society. When the Directorship of the Vatican 

 Observatory was taken by Father Denza a very 

 comprehensive programme was drawn up, embracing 

 investigations in meteorology, terrestrial magnetism, 

 geodynamics, and astronomy. Observations in each of 

 these branches of knowledge have increased in number 

 every year since then, and the fourth volume of the 

 Pubblica:ioni of the Observatory, received by us on the 

 same day as the news of Father Denza's death, is even 

 greater in bulk than any of the previous ones. Father 

 Denza was chiefly instrumental in making the Vatican 

 Observatory one of those co-operating in the production 

 of the photographic star-chart. He devoted his best 

 energies to the advancement of the scheme, and to the 

 progress of astronomical photography. The reports to 

 which reference has been made, contain evidence of his 

 knowledge of what had been done in other astronomical 

 observatories, and of his ability to direct and further the 

 advancement of celestial photography. His services to 

 astronomy have earned for him an honoured place in our 

 memory of the sons of science. 



Mr. Ranyard was born in 1845. He was educated 

 at Cambridge L'niversity, and was called to the Bar 

 in 1871. He was one of the founders of the London 

 Mathematical Society, of which he was originally joint 

 secretary with Mr. George De Morgan, Prof. Augustus 

 De Morgan being president. He became a Fellow of 

 the Royal Astronomical Society in 1S64. In 1870 he 

 was assistant secretary of a joint committee of the 

 Royal Society and the Astronomical Society, which 

 organised the expedition despatched to Sicily, Spain, and 

 Oran to observe the total solar eclipse of December 21. 

 On his return to England he undertook to assist Sir G. 

 B. Airy in the preparation of the report of the observa- 

 tions of the total eclipses both of 1870 and i860. Ulti- 

 mately Sir George Airy transferred the work entirely to 

 Mr. Ranyard, and in 1S80 the report was published by 

 the Royal Astronomical Society as vol. xli. of its 

 ".Memoirs." He observed the total eclipse of July 29, 187S, 

 from Cherry Creek, near Denver, Colorado, and the total 

 eclipse of Alay, 1S82, from Sohag, in Upper Egypt. In 

 addition to papers on the corona and matters connected 

 with physical astronomy, he also published papers on the 

 " Early History of the Achromatic Telescope," and on 

 " Photographic Action." In conjunction wiih Lord Craw- 

 ford and Balcarres, he undertook in 1 87 2 a series of 

 experiments on photographic irradiation ; and in 1886 

 he demonstrated by a series of experiments that the 

 intensity of photographic action varies directly as the 

 brightness of the object photographed, and directly 

 as the time of the exposure. The " old and New 

 Astronomy," designed by Mr. Proctor, was completed 

 in 1S92 by Mr. Ranyard, who contributed to it some 

 very important sections on the structure of the stellar 

 universe. 



NOTES. 

 The newly-discovered gas is to be the subject of a discussion 

 at a meeting of the Royal Society on January 31, when Lord 

 Rayleigh and Prof. Ramsay will present their paper. This 

 will be the first meeting under a resolution of the Council of 

 the Society passed last session, whereby certain meetings, not 

 more than four in number, are to be devoted every year, each to 

 the hearing and consideration of some one imporiant communi- 

 catioD, or to the discussion of some imporiant topic. 



