PREFACE 



This book describes a system for coding biological responses to chemicals. It is published in 

 two volumes, a Biology Code and its attendant Key. Both were developed by the Chemical- Biological 

 Coordination Center of the National Academy of Sciences- -National Research Council in the course of 

 its work of organizing a large mass of chemical- biological data as described hereafter in the Introduc- 

 tion to the Code. 



Established in 1946, the Chemical- Biological Coordination Center set out to develop methods 

 for coding information on chemical structures and biological responses. Its ultimate aim was to pro- 

 vide both a repository for such information and means for machine searching of the stored data. Its 

 founders were emboldened by the expectation that if information of this kind could be coded on a large 

 scale, machine methods would provide an important research tool for discovering and exploring corre- 

 lations between chemical structure and biological activity. 



The concept of the Center had its roots in a widely felt need for ways to deal effectively with 

 the growing mass of chemical- biological data, both published and unpublished. 



Pertinent experience had been gained during World War II by the testing program of the Insect 

 Control Committee of the Office of Scientific Research and Development. The late Dr. Milton C. 

 Winternitz, in particular, recognized the potential of that program and its possible extension with 

 machine aids to the general field of chemical- biological relationships. With his characteristic dynamic 

 enthusiasm he developed the idea of the Center and guided its establishment as a broad experimental 

 undertaking in the service of science. 



The first essential step was the design of coding systems, one for chemical structures and one 

 for biological responses. Newly developed accounting machines were available, and it was decided 

 that punched card, machine sorting techniques should be used. 



To devise a coding system for chemical structures was the easier of the two tasks. C. Chester 

 Stock directed the development of the Chemical Code, which was based on an existing scheme, the 

 Frear chemical coding system, selected as a pattern because it was designed for punched cards and 

 was therefore adaptable to machine sorting. As developed by the Center the chemical code was ulti- 

 mately used to record the structures of approximately 63, 000 compounds. It was published by the 

 Academy- Research Council in 1950 under the title, "A Method of Coding Chemicals for Correlation and 

 Classification. " Except for a few extensions it was not subsequently modified. 



Construction of a coding system for biological responses proved to be more difficult. In 194 6 

 the Center took over, as its Biological Codification Panel, the Biological Codification Committee which 

 had been established under the chairmanship of McKeen Cattell by the OSRD Insect Control Committee. 

 Given the task of devising a satisfactory biological coding system, this Panel carefully reviewed the 

 suggestions of various CBCC subcommittees and in 1950, through the devoted efforts of Raimon Beard, 

 who agreed to assume the immediate direction of the undertaking, a functioning code was established. 



Comprehensive studies showed that workable coding procedures had been evolved, and the pro- 

 gram of storing chemical and biological data went ahead. The Center collected and coded published 

 data from the periodical literature and unpublished data from screening programs of various agencies, 

 including those participating in the Center's own screening program. A total of some 220, 000 punched 

 cards were eventually put into the Center's files, each representing one "unit of information", that is, 

 one biological response to one chemical. These cards were coded from more than 75, 000 "code sheets", 

 each containing data from one source of information on the biological responses of one chemical. 



Those who used the Biology Code soon realized that the complexities of coding biological re- 

 sponses were such that an explanatory guide would be necessary if the coding and interpretation were 

 to be uniform enough to insure efficient retrieval. Thus the Key to the Biology Code was progressively 

 developed as coding experience grew. Also, the Code itself went through a number of revisions as 

 corrections, additions, deletions, and annotations accumulated steadily. 



Despite the loyalty to the Center of agencies inside and outside the Federal Government, which 

 provided financial support through its formative stages and the beginnings of larger- scale operations, 

 funds could not be found to permit its growth to proportions that were considered necessary for its ef- 

 fectiveness, and the Center was regretfully terminated by the Academy- Research Council in 1957. 



