An examination is made of the orthogonal turbine and its application to low-head hydroelectric stations. Experiments showed that the efficiency of the turbine depends on many factors, the main ones of which are the form of the blade profile, quality of its manufacture, and configuration of the straight-flow turbine pit, especially at places of its maximum narrowing. The maximum efficiency of the turbine attained on this device was about 0.5 and this under the condition that the turbine shaft rotated in plain and not rolling-contact bearings. This is not essential for comparative experiments for developing designs, but is essential for an absolute evaluation of the maximum efficiency of turbines. In the case of rolling-contact bearings, reducing the mechanical losses, the maximum efficiency of the turbine would apparently increase to 0.55-0.60.