<br />
 But that&#39;s not what you asked, the first ACCURATE measurement.  You asked who was the first to measure the speed of light.<br />
<br />
Olaf Roemer did  a very good mathematical estimate based on the planets and the earths rotation, but in 1849 Hippolyte Fizeau did a mechanical measurement that established the  speed of light at 196,325 miles per second.  A little out, but still really close.<br />
Foucalt was an &quot;expert&quot; on the properties of the pendulum.  He took Fizeau&#39;s mechanism and made it more accurate.  Foucalt is probably more well known for his pendulum theories proving the earth&#39;s rotation.  Foucalt was a student of Fizeau.  Isn&#39;t the internet wonderful.  Thank you Al Gore. <img src='http://www.cruisecrazies.com/community/images/forum/tr-emoticons/tongue.gif' class='bbc_emoticon' alt=':tongue:' /> <br />
Your call.<br />
These guys were so smart that the Nobel prize for science would be an insult.