. Journal of electricity. d intensity of illumination. From Fig. 2it is seen that the diameter of the beam would be 105feet. Undoubtedly this would result in an area lightgreater than ordinarily could be expected. By interpolation, however, it can be seen thatwith a 15° spread of beam the intensity of illuminationwill be about 1 foot candle and after making the cor-rection, foot candles of useful light will reach thewall to be lighted. This is a value close enough forthe work in hand, that is, for ordinary work onwharves, for patrolmens use around factories,bridges, etc. 300 JSO #)0 450 SC
. Journal of electricity. d intensity of illumination. From Fig. 2it is seen that the diameter of the beam would be 105feet. Undoubtedly this would result in an area lightgreater than ordinarily could be expected. By interpolation, however, it can be seen thatwith a 15° spread of beam the intensity of illuminationwill be about 1 foot candle and after making the cor-rection, foot candles of useful light will reach thewall to be lighted. This is a value close enough forthe work in hand, that is, for ordinary work onwharves, for patrolmens use around factories,bridges, etc. 300 JSO #)0 450 SCO 350 600 650 700 75$ 800 650 %)0 2i>C /OOflDistance fromPrejecfor /rj f^eerFIG. 4—INTENSITY OF ILLUMINATION FROM 300 TO 1000 FEETFROM THE LIGHT SOURCE From Fig. 3 it is seen that at 300 feet the intensitywith a 10° spread and no losses considered is footcandles. This is more than was decided to be neces-observations taken previous to making the calculation,the useful light falling on the wall will be foot. THE BENSON POLYTECHNIC HIGH SCHOOLThis modern and completely equipped plant was made possible by the generosity ot Benson of Portland who donated $100,000 with the provision that the city furnish alike sum for its erection. TRAINING THE YOUNG ELECTRICIAN (This model trades school of Portland, Oregon, is anexample of what we might have in other western citiesto prepare our boys to take that position between menof the ranks and professional men for which so littletraining is offered under our present system.—The Editor.) The first public trade school was opened in Port-land, Oregon, in the fall of 1908 with an enrollment of127, in some old buildings formerly used for grammarschool work. Today the school shows a day andevening enrollment of over 1000 and is housed in oneof the largest and best equipped buildings of its kindfound anywhere in the west. The site of the newschool comprises six city blocks. In response to the growing public sentiment, that
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