In terms of relative length of units, a yoctometre ranks as follows: Planck length yoctometre zeptometre. A yoctometre is 1/1000 of a zeptometre (1 zeptometre (zm) = 1,000 yoctometres). The yoctometre,is the distance light travels in about:1Ã·2.99Ã10 35 seconds.
Engines of various sorts have been invented over the last two or three centuries. 1  In 1698, English military engineer, Thomas Savery, invented and patented the first crude steam engine, based on Denis Papin's Digester (pressure cooker) of 1679.
The steam engine was not so much invented as developed. To give credit to any one person would be to steal credit away from its many rightful owners. The steam engine was developed over a period of about a hundred years by three British inventors. The first crude steam powered machine was built by Thomas Savery, of England, in 1698. Savery built his machine to help pump water out of coal mines. This machine was so simple that it had no moving parts. It also used up lots and lots of coal just to pump a small quantity of water.