5. CHEMICAL INSTRUMENTATION 



D. E. Carritt 



1. Introduction 



One of the relationships of chemistry to other sciences has often been likened 

 to that of a handmaiden, ever present and ready to provide needed information 

 and services. In oceanography, the results of applying chemical techniques and 

 principles to obtain a better understanding of various isolated systems in the 

 ocean show up the utilitarian aspects of chemistry and, at the same time, 

 provide rather clear evidence of the inter-relationships and the extent of 

 coupling between the biological, physical and geological parts of the systems 

 functioning in the oceans. 



Much of the science of oceanography is concerned with the study of processes 

 in which there occurs a transfer of energy and of matter. Analytical and 

 physical chemistry deal with measurements of the quantities and states of 

 matter and of energy. It is quite natural, then, that much of the primary 

 information which is assembled and analyzed to provide us ultimately with a 

 model we believe to be a description of the real oceans comes from chemical 

 measurements. 



Many of the chemical measurements made in pursuit of the model building 

 utilize procedures, techniques and instruments that are common to many 

 other kinds of studies that depend upon chemical analyses. For example, the 

 techniques and instruments used during the spectrographic analysis of marine 

 sediments are essentially the same as those used during the analysis of a wide 

 variety of samples of non-marine origin. That is, many measurements are in no 

 way characteristically oceanographic, except for the origin of the sample. 



No attempt will be made in the following discussion to review and evaluate 

 the instrumentation associated with all of the kinds of chemical measurements 

 that have been made in oceanography. Rather emphasis will be on the in- 

 strumentation that has been developed, and, in some cases, might be developed, 

 to solve measurement problems in situations where the oceans place unique 

 restrictions and requirements upon the way in which the measurements are 

 made. Detailed descriptions of mechanisms, circuits and operating procedures 

 will be omitted. These are adequately covered in the original literature. 



The record of a symposium on oceanographic instrumentation (NAS- 

 NRC, 1952) provides a discussion of all oceanographic instrumentation 

 problems to that time. In the section on chemical measurements {op. cit., 

 chap. X, p. 166) it was pointed out that instrumentation problems appear in 

 three broad categories, i.e. shipboard measurements; measurements in shore- 

 based laboratories ; and in situ measurements using unattended recording or 

 telemetering buoys, as well as from a research vessel. Unique problems appear 

 in the same categories today. Some of the problems noted in 1952 have been at 

 least partially solved. Some of the instrumentation suggested in 1952 has been 

 found to be inadequate or techniques not obvious at that time better suited to 

 the problem. In short, advances have been made. 



[MS received October, 1960] 109 



