On Sat, 16 Jul 2011 23:28:13 -0700 (PDT), harry
wrote:

On Jul 16, 9:27*pm, Andy Dingley wrote:
On Jul 16, 7:07*pm, harry wrote:

On Jul 16, 10:24*am, Guy Gorton wrote:
No that is correct. They had huge pistons and very long strokes.

Early steam engines actually ran on vacuum.http://en.wikipedia.org/wiki/Atmospheric_engine

FFS! *Don't believe _anything_ on Wikipedia!

The staem was used to flush air out of the cylinders.

Er no, the air was displaced by the steam being fed into the cylinder.
Get your intentions and consequences in the right order.

When it was
condensed (By a water jet) the piston was"sucked down"by the resultant
vacuum.
Hence "atmospheric."

So some a litte boy would

Que ?

operate the valves manually. A big advance
was automatic operation.

Don't you know anything?