Abstract: A method and apparatus for monitoring stack gas emissions wherein a probe including temperature and pressure indicating transducers is sequentially located at predetermined positions within a smokestack and the output of such transducers is fed into an electronic data logger for retention therein. The data logger includes a light hand held module having a liquid crystal display and start/reverse/advance pushbutton switches whereby the data logger can be remotely controlled. The invention eliminates the necessity of using two operators to record the desired information and significantly reduces the cost of producing accurate evaluation of stack gas emissions.