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Tn 1875 Father Perry instituted a regular series of drawings of the 

 m:u kings on the Sun from a projected image of 10 inches diameter, 

 formed on a drawing board attached to the telescope. This work 

 was supplemented by spectroscopic examination and measurement of 

 the chromosphere and prominences, and after 1882 by systematic 

 spectroscopic observations of Sun spots. In addition to the researches 

 in solar physics, in connection with which the name of Father Perry 

 has become so well known, the ordinary work of an observatory has 

 been most diligently carried on at Stonyhurst, the results of which 

 for the most part have been recorded in the publications of the Royal 

 Astronomical Society. 



It was not, however, in his work in the Observatory and College 

 tliat Father Perry found an outlet for his untiring energy. His 

 services were always at the disposal of scientific societies, and he 

 took part in nearly every astronomical expedition of his t ; me, an 1 

 although a martyr to sea sickness, he was always ready and willing to 

 undertake any voyage and undergo any hardship in the cause of the 

 science he loved. 



His first important scientific work was done in 1868, when, in con- 

 junction with Father Sidgi-eaves, S.J., he made a magnetic survey of 

 the West of France. With the Stonyhurst instruments complete sets 

 of observations were made at fifteen stations during that year, and 

 the work being continued the year following observations were obtained 

 at nineteen other positions in the East of France, and thus a valuable 

 and reliable magnetic survey of that country was completed. In 

 1871, assisted by Mr. W. Carlisle, of Stonyhurst, Father Perry 

 carried out a similar work in Belgium, where the disturbing effect of 

 the coal measures was very clearly indicated in the results obtained, 

 which, together with those of the survey of France, were published 

 in the ' Philosophical Transactions of the Royal Society.' 



In 1870 Father Perry was appointed chief of the Solar Eclipse Ex- 

 pedition to Cadiz, his work being principally spectroscopic ; and in 

 1874 he was selected by the then Astronomer Royal, Sir Gr. B. Airy, 

 to take command of the Transit of Venus Expedition to Kerguelen 

 Island. On September 20th he and his party left the Cape of Good 

 Hope for Kerguelen Island in H.M.S. " Volage," on a journey attended 

 by great difficulties and dangers, owing to the fearful weather usually 

 prevailing off Kerguelen Island. Intense as must have been the 

 suffering of Father Perry during the voyage, and severe the hardships 

 of a nineteen weeks' sojourn on the " Island of Desolation," as he 

 called it, all were cheerfully borne, every personal consideration being 

 sacrificed to the astronomical interests of the Expedition. The 

 observations of this transit were imperfect on account of haze, and 

 the necessity of determining the exact longitude of their station pro- 

 longed the visit of Father Perry and his companions until February 



d 2 



