Fire Alarms by Flashes of Sunlight.
Experiments are being made this summer with standard heliographs such as are now used in the army for signalling in the national forests. One of these experiments will be on the Kanikeu national forest in Idaho, and the other on the Stanislaus forest in California. It is intended to discover whether such instruments will be of use in reporting forest fires and in the transmission of other messages in areas where there is no quick method of communication. Conditions of climate and latitude as well as the species of inflammable trees in the two forests are sufficiently different to determine whether the instrument is suited to some localities and not to others. There are 195,000,000 acres in the national forests, and telephones have already been successfully used in reducing fires to a certain minimum. It is believed the heliograph can greatly supplement the telephone in this work. There are 148 national forests in 19 States and Territories. During the last year 3,400 miles of trails, 100 miles of wagon road, 3,200 miles of telephone and 40 miles of fire lines have been constructed in these forests.