4.56 Scientific Proceedings, Royal Dublin Society. 
Drawings of Mars from 1877 are also contained in the following 
papers :— 
J. L. E. Dreyer: Notes on the physical appearance of the planet 
Mars, as seen with the three-foot reflector at Parsonstown, during 
the opposition of 1877. (Transactions Royal Dublin Society. New 
Series. Vol. I., Part 6). 
L. Niesten : Observations sur l’aspect physique de la planéte Mars 
pendant l’opposition de 1877. (Ann. de l’Obs. de Bruxelles. 
SUA E TB) 
The first of these papers contains twelve views, which are in 
very fair accordance with Mr. Green’s. M. Niesten published 
thirty-nine drawings, very well executed in chromolithographs. 
They were made between August 21st and November 10th, with 
a six-inch refractor, but do not show quite as much detail as those 
already mentioned. 
In 1879 Mars was also very favourably situated, especially for 
an examination of the equatorial regions. Mr. Green writes to The 
Observatory that some of his drawings show “ faint and diffused 
tones” in places where M. Schiaparelli informs him he has during 
this opposition seen new canals. Mr. C. E. Burton has chiefly 
with an eight-inch silver-on-glass reflector made about twenty 
drawings, and on many of these narrow canals like those seen at 
Milan appear. The author of the present record has with the 
Dunsink refractor seen two or three similar objects on two nights 
when the definition was exceptionally good.* 
The Satellites of Mars have been regularly observed by Pro- 
fessor Hall since October 12th. He found that Phobos arrived at 
its elongations forty-four minutes before the predicted times, the 
error in areocentric longitude of the ephemeris being + 84°3 
(rather less than the estimated probable error), so that the time of 
revolution must be shortened by 1°074, thus becoming 75 39™ 
13°'996. The ephemeris for Deimos is in excellent accordance 
with the observations. Both Satellites have been observed by 
Mr. Common with his new three-foot reflector, and by Professor 
Young at Princeton, N.J., with a nine and a half-inch object- 
*Mr. Burton’s paper (in which two drawings of mine are included) is published in 
the Transactions Royal Dublin Society. New Series. Vol. I. Part 12. 
