18 H. A. LENEHAN. 
varying illumination ; but after all, it is quite certain that 
intrinsic growths of dusky matter have taken place, and 
as no mineral is known which could give this appearance, 
it is ascribed to the growth of vegetation. As the 
lunation progresses the western portion of the dark area 
slowly fades out, and the eastern is absorbed in the 
growing shadows of the lunar night. A more detailed 
account of the phenomena will be found in Harvard College 
University Annals, Vol. 53. In a paper called “‘The reality 
of supposed changes on the moon’s surface,’’ M. Puiseux 
discusses at some length the various observations of 
alleged changes on the lunar surface under the influence 
of the solar radiation. Going back to the earliest 
observations of details, he considers each authoritative 
report of suspected change up to the most recent 
observations of the reported increase of the diameter of 
Linné during lunar eclipses. Summing up the evidence 
thus examined, M. Puiseux arrives at the conclusion that 
the case for real changes taking place on the surface of 
our satellite is not established. He believes that the 
change of sensitiveness of the retina when observing faint 
objects is sufficient to account for the changes usually 
observed, whilst the different conditions of exposure 
when photographing the eclipsed moon might easily 
introduce the changes suspected from the examination 
of photographs. 
Mars.—Mr. G. D. Hirst, F.R.A.S., who was president of 
the New South Wales branch of the British Astronomical 
Association 1904-1905, during the 1905 opposition of the 
planet Mars, obtained some good drawings of more than 
special interest, and has been pleased to. give the 
Observatory copies from which lantern slides have been 
made and colored very delicately, but no signs of the 
canals were shown with the optical facilities he possessed. 
