112 



M inni.KTdX, Crntriu<! Microscopr Objccth'cs 



rVift. Nat. 

 I. Vol. 73 



is then screwed into place and the image-forming rays from the lamp are 

 raised slightly to form an image on the second lens. The objective should 

 then be tightened or loosened until this image also remains stationary. Should 

 it be too loose, and therefore liable to unscrew, a little celluloid dissolved 

 in ethyl acetate until it is the consistency of golden syrup may be put on in 

 two tiny spots on opposite sides of the lens mount by means of a pin. l."se 

 as little as possible of this mixture, as it may run into the threads and 

 prevent the objective from being unscrewed again, 



As advised in the article, all high power objectives should be left for an 

 instrument maker, as they require much more accurate centring and the 

 graticule image is, in this case viewed through a fairly powerful reading 

 telescope. 



■ • 



Lamp and Centring Device 



LETTER TO EDITOR RE REPORTED BURIAL MOUND AT SUNBURY 



Murraba, Coldstream, Vie. 

 September 26, 195o 

 Hon. Editor, 

 The / icforidn Xaturalist 



Dear Sir, 



The mound on Mr, Webb's property near Sunbury, described by Mr. Brun- 

 ton in the September issue of the 1'icforiau Xaturalist, was investigated in 

 1934 by myself and the late D. J. Mahony, then Director of the National 

 Museum. We had heard it was reputed to be a native burial mound, and as 

 such things are otherwise unknown in Australia, we carried out a fairly 

 detailed examination of it. Mr. Mahony was a geologist of some standing, and 

 I had had some experience of archaelogical excavation. 



