Hi all
apologies for the size of the e-mail but thought you would like to know that
the automatic door is not a new principle. According to Jackie Sinclair from
the Guild of Architectural Ironmongers (UK) in an article in the Architect's
Journal supplement the AJ Focus (March 2001 page 34) she shows a picture of
an automatic temple door invented by Herodias of Alexandria using an
aeolipile principle more than 2000 years ago. I have attached the diagram
scanned into a Word document, although the quality of image is not great.
Anyone wanting a better copy I can send you a hard copy in the post if I
have your address.
The principle seems to be to have the temple doors fixed to rotating pillar
type foundations below ground. These subterranean pillars are connected by
ropes and pulleys with counter balance weights at one end and the other to a
bucket via a pulley. The bucket has a tube and siphon system to a sphere
adjacent to it and in the sphere is filled with water to halfway point. All
this equipment is below ground level. The sphere has a tube extending up
through the ground to an above ground column on which is placed a fire.
Presumably with my limited knowledge of physics the principle was that the
fire drew oxygen from the sphere creating a vacuum which would then be
replaced by the water sucked out of the bucket. The bucket becomes lighter
than the counter balance weight and thus the rises causing the ropes to
rotate the pillars and open the temple doors.
Guess it must have been a bit of a slow job getting a fire lighted every
time you wanted a door opened to the temple but probably caused quite a bit
of excitement to the crowd to see the doors open on there own.
Sorry of this seems trivial to the list but may be a good way to tell your
client that automatic doors are not a new invention.
cheers
marcus
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