372 Canadian Record of Science. 
labours in such observatories where observations are continually 
adjusted to the day. . . . While the Directors of the Pulkowa 
Observatory make their full acknowledgment to the Astronomer 
Royal for this precedent, which has been established, so are they 
ready to follow the example, and this fact leads us the more to 
expect that also this course will be adopted by the Washington 
Naval Observatory, as in the American Marine the Date Notation 
from midnight has been already accepted. It is only in the 
matter of the period when the Date Notation, according to Universal 
Time, should be introduced into the publications of the observato- 
ries, that we feel inclined to recommend that there should be delay 
until, in this respect, the most perfect possible understanding be 
attained by all astronomers, in order to avoid the much more 
critical disturbance in astronomical chronology which would arise 
if the transition to the new Date Notation was not equally followed 
on all sides. We are desirous, accordingly, of suggesting a suitable 
time-point for the commencement of the year for which the 
Nautical Almanac would inaugurate the changes corresponding to 
the requirements named. ‘The latter, as has before been said, 
could come to pass in the year 1890. We would, however, ourselves 
prefer the change to take place, in the first instance, with the 
change of the century. Until that date it would probably be the 
simultaneous proceeding of all astronomers, with general consent, 
to look forward to this period of transition, and it would more 
easily stamp itself on the memory of all who hereafter would be 
busied in investigation in which exact chronology plays a part.— 
Paper on the Washington Conference by Otto Struve, Director of the 
Imperial Astronomical Observatory, Pulkowa, Russia. 
II]. The reasons for making the change, as affecting astronomers, 
are :—(1) The introduction of the Universal Day commencing at 
Greenwich Midnight, and reckoning from 0 to 24 hours makes it 
inexpedient to have another time reckoning of 0 to 24 hours starting 
from Greenwich Noon. There are already frequent mistakes of date 
arising from confusion between civil and astronomical reckoning, 
several practical observers using the f.rmer, which is also common- 
ly employed in almanacs and occasionally in some astronomical 
periodicals. The use of three different systems of reckoning solar 
time would greatly increase the confusion. (2) The circumstances 
_ under which astronomical observations are made have completely 
changed in modern times since the application of powerful telescopes 
to meridian instruments and the development of Solar Physics. 
The change of date at noon in the middle of the day’s work has 
thus, in many cases, become very inconvenient. (3) As regards 
