<s>
The	O
Brenkert	B-General_Concept
Brenograph	I-General_Concept
Jr.	I-General_Concept
was	O
a	O
projector	B-Application
used	O
in	O
atmospheric	O
theatres	O
to	O
project	O
moving	O
clouds	O
over	O
ceilings	O
painted	O
blue	O
.	O
</s>
<s>
The	O
company	O
sold	O
the	O
projector	B-Application
for	O
$225	O
in	O
the	O
1920s	O
.	O
</s>
<s>
The	O
projector	B-Application
operated	O
automatically	O
with	O
a	O
universal	O
electrical	O
motor	O
,	O
capable	O
of	O
varying	O
speeds	O
.	O
</s>
<s>
The	O
projector	B-Application
was	O
small	O
enough	O
to	O
be	O
hidden	O
in	O
the	O
theatre	O
architectural	O
design	O
so	O
that	O
the	O
illusion	O
of	O
floating	O
clouds	O
would	O
be	O
maintained	O
.	O
</s>
