TIME-RECKONING. 129 
tical men. Simply to illustrate one mode, Figures 6 and 7 are 
supplied. 
Fia. 6, 
The object is to indicate cosmopolitan and local time by the same 
watch. Fig. 6 shows the watch case open, with the dial for cosmo- 
politan time exposed. Fig. 7 shows the watch case closed, with the 
local time numerals engraved on the face of the case, the latter being 
pierced in order that the hands may be seen. The local time disc 
is designed to be adjustable for any one of the 24 lettered meridians. 
By this arrangement only the local hours would vary ; there would 
be a complete coincidence in the minutes of cosmopolitan and local 
time at every station. The application of double dials to a watch 
may be effected in another manner. The watch may have two faces 
back to back; one for for cosmopolitan time, the reverse for local 
time, the hands in both instances being moved by the same wheel- 
work, and those for local time supplied with the means of adjustment 
for change of longitude. 
The latter plan has advantages peculiar to itself, Other methods 
of construction may be proposed, but it is unnecessary ; the present 
object is simply to show that there is no practical difficulty in the 
way of carrying the scheme of time reckoning set forth in the accom- 
panying paper into the practice of daily life. 
9 
