APPENDIX A 



I. THE BIOLOGY IBM PUNCHED CARD 



It will be noted that the standard IBM card (Figure 1) is divided into 80 columns in each of which 

 are printed the numbers 1 through 9 and, at the top of the column, 0. Thus, it may be immediately ap- 

 parent that in each column there are at least ten positions for perforation, representing ten available sym- 

 bols. The machines can make two additional perforations at the top of the columns beyond the position. 

 These are referred to as the II and 12 positions on the column. Therefore, in all, there are actually 

 twelve basic punching positions in each column, representing twelve available symbols. 



It is possible to multiply the number of symbols available in any one column by using the three 

 upper positions of the column (0, 11, and 12) as designators for combination with any one of the remain- 

 ing number positions. This permits the 26 combinations which are assigned the letters of the alphabet 

 as symbols. Figure 1 illustrates each punch and punching combination which can subsequently be dis- 

 tinguished and interpreted as a symbol. While any or all of these may be used in any one column of the 

 card, each is illustrated in a separate column in the figure, with the interpretation at the top of the col- 

 umn. In each of the first twelve columns, the card in Figure 1 is punched with only a single punch, the 

 punching being interpreted, at the top of the card, as numerical symbols 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 

 11, and 12. In Columns 22 through 39 and 41 through 48, the punching illustrates combinations of po- 

 sition 12, 11, or with position 1, 2, 3, 4, 5, 6, 7, 8, or 9, this punching being interpreted, at the 

 top of the card, as letters A through Z. It will be noted that the combination of punches in positions 

 and 1 is not made, due to the proximity of the two perforations in the same column; punching in adjacent 

 positions in the same column is never recommended, to prevent any possible confusion in machine inter- 

 pretation and sorting. 



The three topmost punching positions (12, 1), and 0) are commonly referred to as "zone punches", 

 the remaining ("low") positions in the column being the "digit punches". The former are sometimes re- 

 ferred to as the "first", "second", and "third" zone punches, but throughout the Code and Key they are 

 referred to as the "12", "11", and "0" zone punches, respectively. 



In addition to using the zone punches in combination with digit punches for 26 alphabetical sym- 

 bols, it is possible to assign definitions to each of the zone punches alone; in other words, the 0, II, 

 or 12 position could be punched, uncombined with any numerical punch, to indicate a specific meaning 

 assigned to that single punch, as well as being used in combination with digit punches to indicate a 

 specific meaning assigned to that combination. In that case, the number of available symbols in any 

 one column would be 38 (1 through 9, A through Z, and the 3 zone punches used alone). The CBCC , 

 however, has never used any zone punch alone as a symbol when it has been used already as a desig- 

 nator for letter symbols. Therefore, in the case of the CBCC Biology Code, any one IBM punched card 

 column may be considered to be limited to a maximum of 3 5 symbols each. Reference to the following 

 list will make clear the number of symbols available to the CBCC in any one column, according to the 

 use made of the zone punches. 



Number of symbols 

 available in one 

 Symbols used column 



1 through 9 and A through Z (no zone punches used alone) 35 



1 through 9, A through R, and the zone punch used alone 28 



1 through 9, J through Z, and the 12 zone punch used alone 27 



1 through 9, A through I, S through Z, and the 1 1 zone punch used alone ... 27 



1 through 9, A through I, and the 1 1 and zone punches used alone 20 



1 through 9, S through Z, and the 12 and 11 zone punches used alone .... 19 



1 through 9 and the 12, 11, and zone punches used alone 12 



Some types of information need fewer symbols than others. Consequently, the pattern of zone 

 punch combinations with digit punches (one of the seven above) varies from column to column, according 

 to the information category, though it can not vary within a given column once it is established. The 

 first of the seven possible combinations might be appropriate for information coded in one column 

 (because more than 28 symbols are needed for the category of information coded in that column), while 

 the second or third or any other of the last six possible combinations could be established for informa- 

 tion coded in another column (if 28 or fewer symbols are adequate for that particular information category). 



When a zone punch is not used for combinations with the numerical punches (any of the last 

 six possibilities of the seven listed above), the CBCC has considered it to be available for a specific 

 definition, if needed. However, if a special meaning is assigned to a zone punch, the CBCC considers 



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