KEW OBSERVATORY 165 



presented to the Kew Observatory by the Royal 

 Society. 



' In the dome is placed the photoheliograph 

 for obtaining pictures of the sun's disk ; attached 

 to the dome there is a small chamber in which the 

 photographic processes connected with the photo- 

 heliograph are conducted. This chamber is supplied 

 with water by means of a force-pump. A self- 

 recording Robinson's anemometer is also attached 

 to the dome. 



6 In addition to the rooms now specified, there are 

 the private apartments attached to the observatory. 



' On the north side of the observatory there is 

 an apparatus similar to that used at the Toronto 

 Observatory for containing the wet- and dry-bulb, 

 the maximum and the minimum thermometers. 



' The model magnetic house . . . stands at a 

 distance of about 60 yards from the observatory ; 

 and the small wooden house in which the absolute 

 magnetic observations are made, at a distance of 

 about 110 yards. These houses are within a wooden 

 paling, which fences them off from the remainder 

 of the park, and encloses about one acre of ground 

 attached to the observatory. 



6 The work may now be briefly specified. In the 

 first place, the self-recording magnetographs, as already 

 mentioned, are kept in constant operation, and record 

 the changes continually occurring in the magnetic 

 elements. 



' The photographs are sent to General Sabine's 

 establishment at Woolwich, to undergo the processes 

 of measurement and tabulation. . . . 



' In the house for absolute determinations, 

 monthly values of the declination, dip, and horizontal 

 magnetic force are taken, and magnetic instruments 



