A simple method for obtaining a continuous record of the presence and type of clouds in the sky during the day

Summary A photovoltaic cell or solar cell suitably mounted to look at a small portion of the sky and connected to a sensitive recorder yields considerable information as to the condition of the sky. The author has used such a simple device for many years and it is found that familiarity with the type of trace, which is in response to the changes in reflected light from clouds, will permit a good estimate of the type of clouds that are present. The presentation of such cloud information on a standard potentiometer or galvanometer type recorder is very convenient when correlating cloud conditions with other variables being recorded on similar types of recorders.