<s>
The	O
IBM	B-Device
Naval	I-Device
Ordnance	I-Device
Research	I-Device
Calculator	I-Device
(	O
NORC	O
)	O
was	O
a	O
one-of-a-kind	O
first-generation	O
(	O
vacuum	B-Architecture
tube	I-Architecture
)	O
computer	O
built	O
by	O
IBM	O
for	O
the	O
United	O
States	O
Navy	O
's	O
Bureau	O
of	O
Ordnance	O
.	O
</s>
<s>
The	O
Naval	B-Device
Ordnance	I-Device
Research	I-Device
Calculator	I-Device
(	O
NORC	O
)	O
,	O
was	O
built	O
at	O
the	O
Watson	O
Scientific	O
Computing	O
Laboratory	O
under	O
the	O
direction	O
of	O
Wallace	O
Eckert	O
.	O
</s>
<s>
Its	O
design	O
influenced	O
the	O
IBM	B-Device
701	I-Device
and	O
subsequent	O
machines	O
in	O
the	O
IBM	B-Device
700	I-Device
series	I-Device
of	O
computers	O
.	O
</s>
<s>
The	O
machine	O
originally	O
used	O
Williams	B-General_Concept
–	I-General_Concept
Kilburn	I-General_Concept
tubes	I-General_Concept
for	O
memory	B-General_Concept
which	O
stored	O
2,000	O
words	O
electrostatically	O
,	O
with	O
an	O
access	O
time	O
of	O
8	O
microseconds	O
.	O
</s>
<s>
NORC	O
used	O
four	O
sets	O
of	O
66	O
electrostatic	O
tubes	O
in	O
parallel	O
for	O
memory	B-General_Concept
.	O
</s>
<s>
An	O
upgrade	O
to	O
the	O
addressing	O
circuitry	O
for	O
the	O
Williams	B-General_Concept
tubes	I-General_Concept
allowed	O
memory	B-General_Concept
per	O
tube	O
to	O
be	O
expanded	O
from	O
500	O
bits	O
to	O
900	O
bits	O
,	O
expanding	O
the	O
total	O
memory	B-General_Concept
to	O
3,600	O
words	O
without	O
needing	O
to	O
add	O
any	O
more	O
Williams	B-General_Concept
tubes	I-General_Concept
.	O
</s>
<s>
At	O
some	O
point	O
the	O
Williams	B-General_Concept
tube	I-General_Concept
memory	B-General_Concept
was	O
replaced	O
with	O
20,000	O
words	O
of	O
magnetic-core	O
memory	B-General_Concept
,	O
with	O
an	O
access	O
time	O
of	O
8	O
microseconds	O
.	O
</s>
<s>
The	O
speed	O
of	O
the	B-Device
NORC	I-Device
was	O
15,000	O
operations	O
per	O
second	O
.	O
</s>
<s>
An	O
addition	O
took	O
15	O
microseconds	O
,	O
a	O
multiplication	O
took	O
31	O
microseconds	O
,	O
and	O
a	O
division	O
took	O
227	O
microseconds	O
,	O
not	O
counting	O
memory	B-General_Concept
access	O
time	O
and	O
checking	O
.	O
</s>
<s>
With	O
1,300	O
vacuum	O
tubes	O
in	O
the	O
three	O
systems	O
of	O
the	O
computer	O
,	O
the	B-Device
NORC	I-Device
had	O
a	O
total	O
of	O
9,800	O
vacuum	O
tubes	O
and	O
10,000	O
crystal	O
diodes	O
were	O
used	O
.	O
</s>
<s>
The	B-Device
NORC	I-Device
had	O
eight	O
magnetic	O
tape	O
units	O
which	O
were	O
similar	O
to	O
the	O
tape	O
drives	O
on	O
the	O
IBM	B-Device
701	I-Device
system	O
.	O
</s>
<s>
It	O
also	O
had	O
a	O
display	O
unit	O
which	O
consisted	O
of	O
a	O
CRT	O
tube	O
and	O
a	O
35	O
mm	O
film	B-Application
camera	I-Application
which	O
photographed	O
the	O
face	O
of	O
the	O
tube	O
and	O
then	O
sent	O
the	O
film	O
through	O
a	O
develop	O
and	O
fix	O
process	O
before	O
it	O
was	O
projected	O
on	O
a	O
rear	O
projection	O
screen	O
approximately	O
12	O
frames	O
after	O
the	O
initial	O
exposure	O
.	O
</s>
<s>
The	O
main-belt	O
asteroid	O
1625	O
The	B-Device
NORC	I-Device
was	O
named	O
by	O
Paul	O
Herget	O
in	O
honor	O
of	O
the	O
electronic	O
calculator	O
which	O
significantly	O
facilitated	O
the	O
elaborate	O
orbital	O
calculations	O
of	O
minor	O
planets	O
at	O
the	O
time	O
(	O
)	O
.	O
</s>
