The design of automated analysis machines.

: Since the introduction of the first automatic chemical analysis machine 25 years ago, development has progressed rapidly and a wide range of machines are now available. The original machines were constrained by the available analytical techniques, but later developments in methodology have permitted much more latitude. There are four main groups of machines and these differ markedly in operating principles. In addition there are many unclassifiable devices which have been developed for special purposes. The principles underlying the design of the machines are discussed, and as far as possible an account is given of the steps in development which led to their modern form. The principles of fluid flow, which govern the operation of many of these machines, are considered in some detail. Proposals are made regarding the areas in which new development is possible and desirable in the hope of encouraging further work in this field.