A portable salinometer based on direct measurement of the conductivity ratioR_{t}

A new portable salinometer has been developed which is based On a direct determination of the conductivity ratio
R_{t} = (C_{x}/ C_{s})_{t}
of sample
(x)
to standard
(s)
seawater in a dual-cell, continuous-flow system. The new salinometer requires only 10 ml of unknown and much less of standard, drawn from the source bottles through fine Teflon tubes, to obtain complete flushing and several repeat readings to the order of
\pm0.001
, in salinity. The system is autobalancing over the full range of conductivity ratio from 0 to 1.3 and in the future will be direct reading in salinity units. The amount of standard water required is so low that standard water ampoules, at the rate of l/day, can be used as the source. The method used offers a possibility of a direct measurement of salinity in the ocean by measuring
R_{t}
in situ.