Show PUT ON RECORD lick observatory scientists secure valuable records the earthquake of june 11 was per haps the most severe one felt on mount hamilton in the past thirteen years though no damage was done the safety limit must have been nearly reached tb th accompany illustrations are collao of the records traced on the smoked glass plates of two seismographs on that occasion the smaller one was made by an instrument con strutted ted on a very simple plan A massive weight is suspended from the top of the seismograph by means of a slender wire attached to the weight is a multiplying lever carrying a pin point which rests upon a smoked glass ss plate the frame of the inspru ment the fulcrum of the multiplying muti plying lever and the smoked glass plate are rigidly connected and are secured to the top of a massive brick pier run ning down through the floor of the observatory to the solid rock of the mountain motions of the earth are communicated to all parts of the in strument ment except the massive weight which tends to remain fled lied the rel active motion of the framework of the instrument and of the weight to 1 a direct measure of the earth s displacement to make the record more legi ble the lever carrying the point which traces the curve Is designed to mul the earth s displacement by 4 12 1 2 it will be seen from the illustration that the movement of the earth was very complex and in all directions for some reason the east and west components seem to have inflicted the most effective shocks as one of F t ly the fine astronomical clocks whose pend pendulum blum swings in the east and west lost ten seconds of time whereas the other four delicate astronomical clocks with pendulums swinging in the the north and south were not affected |