Abstract: In a rotary gas compressor which has a compression housing, in which the gas compressing elements are operatively confined, a shaft and bearing housing is provided. The latter housing is removably coupled to an end of the compression housing, and supports therein the rotary shaft and the bearings therefor. The bearings are located in a portion of the shaft and bearing housing which is outboard or external of the compression housing. A coolant chamber is set abut the shaft and bearing housing whereat the bearings are located. The latter housing further has apertures formed therein to visually expose the shaft, as well as for discharging therethrough any leaking lubricant.