By way of the practical use of the electrical fishing in salt water, all the data I could collect were carefully compared from the earliest kuehne's studies for protoplasm to the precent kreutzer's for electrotaxis of aquatic animals. The consequences are as follows: All the cold blooded animals are forced to move toward the positive pole in the path of an electrical current flowing from pole to pole which has brought about the possibilities of electrical fishing. This method has been found to be practical in fresh water, but there are some obstacles in utilizing the method in salt water especially because of the large amount of electric power consumed.
In order to remedy the large power consumption, an intermittent current or pulsive current which stimulate the fish most effectively has been tested, but a few electrical quantative values in detail as to the current intensity and wave forms or any quantative results of these experiments have been made public.
According to kreutzer's theory and the above tests, the synthetic observations lead to the conclusion that:
(1) The was form of the pulsive current which gives the fish an electric shock most effectively is an almost right angled triangle with a vertical rise from null and a much slower decay.
(2) The pulses are let repeatedly after recovering shock on the fish as following figure to minimize the large amount of electric power consumption, the recovering provides the next shock effectively by Weber-Fechner's law on psychophysics. Though wave head rises highly vertical, the decaying wave trails and the inter-mittence of electric current prevent the large consumption of power.
(3) The electrotaxis rate among the school of fish is given by Tauti's formula. r=1/√2π σ∫o A log v/voexp{-1/2(x-xo/σ)2dx
Where r is an electrotaxis rate, xo a certain sensibility of fish caused at arbitrary voltage stimulation made electrotaxis, x a mean value of the sensibility of fish at the front of fish school, and A log v/vo a mean value of sensibitity of fish at where the voltage is v by Weber-Fechner's law, where vo is an original voltage, A a constant, and σ a standard deviation.
The electrotaxis rates are given as above if we regards the distribution iof electrotaxis rate as normal.

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