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.
Steam engines were the first engine type to see widespread use. They were first invented by Thomas Newcomen in 1705, and James Watt (who we remember each time we talk about 60-watt light bulbs  and the such) made big improvements to steam engines in 1769.