In this paper is discussed a method of shadow recording for use with reflecting types of oscillographs which simplifies the methods of obtaining time and amplitude rulings on the record. The optical system is rendered portable by the use of a low-intensity light source, compensated by high transmission efficiency. Comparative records indicate that, when used in conjunction with bromide paper, this optical system is of value in recording sinusoidal currents whose frequencies are below 20 cycles per second or currents of complicated wave form whose fundamental frequency is well below 20 cycles per second. No data relative to records on moving film are reported.Mann (1), in discussing a new portable electrocardiograph, has referred to an optical system of this type. The authors believe that the present paper contains sufficient new information on the details of construction and operation of this optical system to make it of value.
Biphasic photolysis of riboflavine with a low-intensity light source.
