Scientists studying environmental processes such as hydrothermal vents and diffuse flows on the ocean floor have a great need for instruments that can analyze data in situ. The solution to that need has been realized in the AIS ISEA III Analytical Instrument Systems, Inc., In-Situ Electrochemical Analyzer from Analytical Systems, Inc., Flemington, N.J. The AIS ISEA III allows for both real-time data collection and data logging in a variety of deployment methods and is capable of performing all types of standard voltammetric experiments, including stripping analysis, in situ. The instrument deploys actual voltammetric electrodes directly into the environment under study and also collects data from pH electrodes, temperature sensors, and standard conductivity and depth sensors. Users can pre-program the instrument using a laptop computer and leave it on the bottom of the ocean, collecting data automatically for several months.