OCR Text |
Show Stone Kept Time. There Is exhibited In the Urltlsh museum a large wtone, composed of carbonate of lluu, which has served as n natural timekeeper. This atone Is, Indeed, an actual time record for the work done for a long period In an English coul mine. Tho stone wns ' removed from n colliery druln. When the miners wure nt work the water passing through the drain left a de-J de-J posit colored black by tho coul dust ; but when no work was done the water I run down cleur and left a white deposit. de-posit. In the course of time these deposits de-posits built up the Mone. Kueh day of work left a black utreuk. Immediately Immedi-ately followed by n white streuk tnmle during the night. Wide white Btreaks Indicate tho holldas and Sundays. |