and vigorously disputed the claims put forward by those who believed that the latter method was the more suitable.  On May 14th, 1679, Halley started for Dantzig, and the energetic character of the man may be judged from the fact that on the very night of his arrival he commenced to make the necessary observations.  In those days astronomical telescopes had only obtained a fractional part of the perfection possessed by the instruments in our modern observatories, and therefore it may not be surprising that the results of the trial were not immediately conclusive.  Halley appears to have devoted much time to the investigation; indeed, he remained at Dantzig for more than a twelvemonth.  On his return to England, he spoke highly of the skill which Hevelius exhibited in the use of his antiquated methods, but Halley was nevertheless too sagacious an observer to be shaken in his preference for the telescopic method of observation.

The next year we find our young astronomer starting for a Continental tour, and we, who complain if the Channel passage lasts more than an hour or two, may note Halley’s remark in writing to Hooke on June 15th, 1680:  “Having fallen in with bad weather we took forty hours in the journey from Dover to Calais.”  The scientific distinction which he had already attained was such that he was received in Paris with marked attention.  A great deal of his time seems to have been passed in the Paris observatory, where Cassini, the presiding genius, himself an astronomer of well-deserved repute, had extended a hearty welcome to his English visitor.  They made observations together of the place of the splendid comet which was then attracting universal attention, and Halley found the work thus done of much use when he subsequently came to investigate the path pursued by this body.  Halley was wise enough to spare no pains to derive all possible advantages from his intercourse with the distinguished savants of the French capital.  In the further progress of his tour he visited the principal cities of the Continent, leaving behind him everywhere the memory of an amiable disposition and of a rare intelligence.

After Halley’s return to England, in 1682, he married a young lady named Mary Tooke, with whom he lived happily, till her death fifty-five years later.  On his marriage, he took up his abode in Islington, where he erected his instruments and recommenced his observations.

It has often been the good fortune of astronomers to render practical services to humanity by their investigations, and Halley’s achievements in this respect deserve to be noted.  A few years after he had settled in England, he published an important paper on the variation of the magnetic compass, for so the departure of the needle from the true north is termed.  This subject had indeed early engaged his attention, and he continued to feel much interest in it up to the end of his life.  With respect to his labours in this direction, Sir John Herschel