accurately ; and we think they will furnish data for a very 
exact determination of the latitude and longitude of the planet 
photographing the transit. These gentlemen report a snow 
storm during the early part of the day, but clear weather in the’ 
afternoon, during whvol a good number of photographs was 
ured. 
Our experience in photographing transits of planets, and in 
measuring the photographs, indicates that while the American 
method is correct in theory, the apparatus needs some change. 
In order to obtain good measures, the picture should be sharp, 
and the exposure short. It is probable, therefore, that the 
reflectors, which now lose about nineteen-twentieths of the 
light, will have to be changed. 
_ A comparison of the observations of contact with the 
eee of the American and English Nautical Almanacs 
shows that the English Almanac is much nearer the truth. 
Since the ephemeris of the American Almanac is based on 
Leverrier’s old theory, and that of the English Almanac on his 
recent one, the result of the present observations appears to be 
a confirmation of Leverrier’s theory with respect to an intra- 
mercurial planet. 
United States Naval Observatory, Washington. 
