41 



and the former agreed to supply a salary to the Professor. Mr Hender- 

 son was selected as the proper person to occupy this situation : and he 

 entered on the duties of the office in October 1834. The value of 

 the observations which he made during the ten years he held this 

 appointment is too well known to need comment. But Mr Henderson 

 did not confine himself to the routine of Observatory duties, important 

 as they are. No sooner had ho got the Institution into working 

 order, than he again vigorously attacked his Cape observations, and 

 laid the results before the world. He commenced by communicat- 

 ing to the Astronomical Society a valuable catalogue of the mean 

 declinations of 172 principal fixed stars for January \. 1837. This 

 was followed by a memoir on the refraction of stars near the 

 horizon, in which he concludes, that no difterence of refraction 

 north and south of the zenith appears as far as to 88° of zenith dis- 

 tance. Another very important communication of Mr Henderson's 

 was the determination of the equatorial horizontal parallax of the 

 moon. TJhis is best effected by the comparison of results north and 

 south of the equator. It is well known, that to obtain it by this 

 method, was one of the chief objects of La Caille's voyage to the 

 Cape in the middle of the last century. Ever alive to the interests 

 of the science, Mr Henderson determined to avail himself of his own 

 position when at the Cape, to repeat the observations. The result to 

 which he arrives is extremely satisfactory, differing as it does but 

 slightly from La Caille's. 



These and similar labours place Mr Henderson high in the esti- 

 mation of astronomers. But something more is requisite to give a 

 man interest in the eyes of the world at large. In the field of 

 science, many a patient cultivator who has conferred a real boon on 

 mankind has been altogether forgotten. The successful opening of 

 some unexplored district, or the discovery of some popularly inter- 

 esting fact, confers, and properly confers, a wide-spread fame. The 

 development of scientific knowledge, as of every thing relating to 

 the preparation of the races of mankind for their future destinies, 

 is regulated by an All-wise hand, which, whilst it dispenses sufficient 

 to satisfy each generation as it passes, kindly holds back an inex- 

 haustible store to supply the intellectual cravings of races yet to fol- 

 low. The natural sciences have not yet (as a philosopher unwisely 

 asserted a century ago they had) nearly attained their ultimate per- 

 fection; and doubtless are not destined soon to do so. Hence, 

 whoever is privileged to make a discovery, however trifling, 

 is worthy of respect, as having contributed towards the fulfilment of 



