1841.] Remarks by Capt. Shortrede, 611 



lar division of the outer card opposite which the given month is to 

 be brought. The meaning is this — instead of the current year 

 division on the outer card marked like the others with two digits, 

 use the division on the left, which being for distinction marked with 

 only the final digit is half blank — opposite this half blank space on 

 the outer card in leap years adjust the January and February months — 

 but never fancy the months to be in any other division than that 

 in which they are written on the inner card. — R. S. 



§ 17. No confusion can arise if it be considered that a single digit 

 7iever represents the current year of a century. For example, the 4th 

 year of the full century 18 is 1804, represented by 04, and not by 

 4 merely. The whole date being expressed by the current year 

 preceded by its full century, if the odd year be written 4 this preceded 

 by 18 becomes 184, being the year 84 of the full century 1. Moreover 

 the puter card has the odd years of a century in their order, i, e. 

 increasing uniformly from left to right, and not at random. — R. S. 



§ 21. The only adjustment required is to bring the division of the 

 middle card containing the full century opposite the division contain- 

 ing 00 on the outer card, and when this is done, no farther adjust- 

 ment of the middle and outer cards to each other can have place 

 throughout that century. — R. S. 



§ 23. These being leap years require according to the direction for 

 January and February (and therefore on January 1st) to have the 

 month division brought opposite the single to the left of the 00, being 

 in that case the half blank to the left. — R. S. 



§ 24. The black dot would require a special explanation, for which 

 there is not room on the back of the card, without confusion or omis- 

 sion of something more important. A total blank would be preferable 

 to a black dot, but to this there would be much the same objection. 



Either of these would derange the principle on which the outer and 

 middle cards are adapted to each other. This principle is, that when 

 the full century for the time being is opposite the 00 or point of ad- 

 justment, every odd year on the outer card is to be read as if it had its 

 proper full century digits before it. The 00 is to be read in the 

 same way as any other year of the century. 



The Table might have been made adjustable by any other zero as 

 well as by 00; and by any other date as by the 1st of January, but 



4h 



