40 ROYAL SOCIETY OF CANADA 
stands by itself. There are, however, many weaknesses in the system, 
chief of which is the practical impossibility of obtaining from it any 
information as to a given book. 
A modification of the Ledger System is what is known as the 
Temporary Slip System. The slips may be used in the same way as 
the pages of the ledger, with the advantage that more than one person 
may be engaged in charging and discharging books. The slips are 
arranged in trays or in pigeonholes in any of three ways: (1) with guide 
cards or blocks for each day, making practically a daybook; (2) by 
borrower's name or number, making an account with the borrower; 
or, (3) by call number, making an account with the book. A sugges- 
tion has been made that by means of a carbon paper, such as is used 
by clerks in a dry-goods store, an extra copy of each slip might be 
made, and thus two records would Le possible, one arranged by bor- 
rowers and the other by books. 
The system most used in American libraries is the Card System. 
This is a further development of the Temporary Slip System. The 
record, being on durable cards, is permanent rather than temporary. 
In other respects the system is substantially the same. As a matter 
of fact, however, there are two card systems —the Single Card Sys- 
tem and the Two Card System. The advantages of the former over 
the Temporary Slip System are comparatively slight; but the Two 
Card System has many important advantages. It is, on the whole, 
the most altogether satisfactory system that has yet been devised. 
There are two sets of cards — borrowers’ and book cards, the latter 
kept usually in date order. The system is subject to a number of 
variations, but the arrangement generally used is that in which the 
borrower’s card records the call number and date, and the book card 
the borrower’s number and date. When a book is returned, the dating 
slip in it and the date of the borrower’s card are compared, and if the 
same, the latter is marked with the date of return and handed back, 
while the book card is looked up by means of the number in the book, 
the date of return is noted on it, the card placed in a pocket on the 
inside cover of the book, or in a card indicator, and the book returned 
to the shelves. 
The indicator, so widely used in English libraries, must also be 
mentioned among charging systems. There are a number of forms, 
and a description of the most popular, known as the “ Cotgreave,” is 
given elsewhere in this paper. 
A feature that is common to some of the indicators as well as the 
card systems, is the movable date register or tray. The date register 
of the indicator has cleven columns for books not overdue, and one 
