Show making a to tre tremble treble ble curious and interesting Is the fact that the be playing of children on the slopes of hill on which the observatory 0 of f greenwich stands fets sets the hill into v vibration to such an extent as to interrupt 0 observations which depend upon the mo ino of a tray of mercury Ilund hundreds reds of children are accustomed in the evening to romp upon the hill outside the observatory walls joining hands they run headlong down the slope and tumble in a heap at its foot the result Is that the solid hill Is thrown into such a state of tremor that tie vibrations continue to be felt at the observatory until long past mid night and for foe many hours after I 1 the he tired children have been asleep youths companion |