1841.] Notes on Capt. Shortredes Scheme. 603 



the same succession in which they stand above, with a few excep- 

 tions. 



16. The exceptions are the leap years, which are advanced one divi- 

 sion to the right of their proper division, for the reason given in Obser- 

 vation 2 of Article 2 : this occasions error in week-days corresponding to 

 January and February, but the scheme says, " in leap years for January 

 and February use the half blank space to the left, then opposite the 

 given date is the day of the week." This is obscure; and, if I un- 

 derstand the author aright, incorrect. The meaning of the author ap- 

 pears to be, " use the division containing May as if January had 

 been there, and fancy February to be where June is." This will lead to 

 error. The direction should be — for January and February in leap years 

 take that day which is one division to the left of the day opposite to 

 the date. The week-day for January and February is one day earlier 

 than the day opposite to the date. 



1 7. Although the leap years are thus advanced, the author of the 

 scheme appears to have left half the digits of the numbers expressing 

 those years in their proper divisions ; for there are four 4s, 2s, and 6s 

 and five 8s in different divisions. This is objectionable, because these 

 numbers may bewilder those who are reckoning for the current years 

 2, 4, 6, 8 ; and, if the scheme be printed for general use, should be 

 omitted. 



18. The middle card of the scheme contains not the centuries 

 of (3) but the full centuries or hundreds of (2) for the convenience of 

 reading. In Table (3) the days of the week for the current years of 

 centuries are shewn in 7 lines : but in the scheme the full centuries 

 and their fixed days revolve in a circle ; and the days are readily made 

 to assume their positions relative to the current years. 



19. If the scheme had a century division, then by adjusting the 

 century division, bearing the name of the week-day commencing the 

 centuries which it contains, with the year division containing the years 

 1, 7, 18, 29, all those years would be shewn to commence with that 

 day ; and the years in the other divisions, with the days standing below 

 them, for those centuries. 



20. But the hundred years or full centuries are more convenient for 

 reading, as years 101, 1801, 1841, &c. ; then the lOOdth year must be 

 so adjusted to a year division that the day on which the following cen- 



4 G 



