Wellington Philosophical Society. 



561 



attached to a hemisphere, which fits into the hemispherical cup containing 



the mercury, a thin film of which supports the platform. The mercury 



can support a weight of 128 lb., or 

 we may say 1001b. without any 

 fear of the mercury spilling over. 

 The platform has a heavy cylindrical 

 attachment which brings the centre 

 of gravity below the bowl contain- 

 ing the mercury. The azimuth circle 

 should be engraved on the upper 

 edge of the hemispherical bowl, and 

 the divisions read by a micrometer 

 attached to the frame or platform 

 on top. A portable almucantar 

 should not be used for general 

 azimuth - work, but the azimuth 

 circle is required as a setting- circle 

 when observing for time or latitude. 

 An ordinary theodolite can be set 

 up on the platform, or a special 

 instrument constructed. In a small 

 model that I constructed, in which 

 the hemisphere and the bowl for it 

 to float in were turned out of wood, 

 the motion was beautifully smooth ; 

 the least touch with the little finger 

 would suffice to turn the instrument 



round, and, if set spinning, it would make a good many revolutions before 



it came to rest. 



2. " A New Method for the Preparation of Ketones," by 

 Professor T. H. Easterfield. 



Exhibits. — 1. Mr. G. V. Hudson exhibited the following : — 



(a.) Three parts of a work entitled " Australian Lepidoptera 

 and their Transformation," by A. W. Scott, with hand-coloured 

 plates ; published in 1864. 



(b.) A series of Dodonidia helmsii, a rare New Zealand 

 butterfly, taken at Silverstream in February, 1907. 



(c.) Two female specimens of Titanornis sisyrota, a gigantic 

 tineid moth not seen alive since 1886, and perhaps now extinct — 

 one taken by Mr. Clement W. Lee, at Otaki, in March, 1886 ; the 

 other taken in Nelson many years ago. The male is unknown. 



(d.) Male and female specimens of Macropathus maximus, a 

 gigantic tree-weta, captured at Kaitoke under the bark of dead 

 birches on the 31st December, 1906 ; originally described by 

 Sir Walter Buller from a single specimen. 



SEPTIOWL VIEyC_.^5 ca le^ 



Third Meeting : 3rd July, 1907. 



Professor H. B. Kirk, President, in the chair. 



Exhibits. — Dr. A. K. Newman exhibited and described a 

 Maori flute and a Maori conch-shell trumpet. 



