**CALCULATOR**

Calculation was a need from
the early days when it was necessary to account to others for individual or
group actions, particularly in relation to maintaining inventories or
reconciling finances. Early man counted by means of matching one set of objects
with another set (stones and sheep). The operations of addition and subtraction
were simply the operations of adding or subtracting groups of objects to the
sack of counting stones or pebbles.

ROMAN ABACUS |

In the very beginning, of course
was the abacus, a
sort of hand operated mechanical calculator using beads on rods, first used by
Sumerians and Egyptians around 2000 BC.

The principle was simple, a
frame holding a series of rods, with ten sliding beads on each. When all the
beads had been slid across the first rod, it was time to move one across on the
next, showing the number of tens, and thence to the next rod, showing hundreds,
and so on (with the ten beads on the initial row returned to the original
position).

John
Napier dramatically advances the understanding of number relationships in 1614
with his invention of logarithms. Since logarithms are the foundation on which
the slide rule is built, its history rightly begins with him. His early concept
of simplifying mathematical calculations through logarithms makes possible the
slide rule as we know it today.

Napier himself contributes Napier’s
Bones in
1617, calculating sticks based on the geologia (lattice) multiplication method.
In 1620 Edmund
Gunter of London makes
a straight logarithmic scale and performs multiplication and division on it
with the use of a set of dividers, or calipers.

CIRCULAR SLIDE RULE |

In about 1622 William Oughtred, an Anglican minister ...
today recognized as the inventor of the slide rule, places two such scales side
by side and slides them to read the distance relationships, thus multiplying
and dividing directly. He also develops a circular
slide rule.

Real Rocket Scientists used slide rules to send Man to the
Moon - a Pickett model N600-ES was taken
on the Apollo 13 moon mission in 1970.

The 17th century marked the beginning of the history of
mechanical calculators, as it saw the invention of its first machines,
including Pascal's calculator. In 1642, Blaise Pascal had invented a machine
which he presented as being able to perform computations that were previously
thought to be only humanly possible, but he wasn't successful in creating an
industry.

Blaise Pascal invented a mechanical calculator with a
sophisticated carry mechanism in 1642. After three years of effort and 50
prototypes he introduced his calculator to the public. He built twenty of these
machines in the following ten years.This machine could add and subtract two
numbers directly and multiply and divide by repetition. Since, unlike
Schickard's machine, the Pascaline dials could only rotate in one direction
zeroing it after each calculation required the operator to dial in all 9s and
then (method of re-zeroing) propagate a carry right through the machine.

STEPPED RECKONER |

In 1674, Gottfried Wilhelm Leibniz creates Stepped Reckoner. The device could add, subtract, multiply,
and divide.

ARITHOMETER |

Thomas’
arithmometer is a mechanical calculating machine designed to perform four basic
arithmetical operations: addition, subtraction, multiplication and division.
This machine was invented by the Frenchman Thomas de Colmar in 1820. This is
the first calculating machine that was commercialized and manufactured in large
quantities. The artithmometer practically dominated sales of calculating
machines during the second part of 19th century. During all his life Thomas de
Colmar was improving it. When he died in 1870, his son Thomas de Bojano, and
later engineer Louis Payen, continued improvements and the production.

A further step forward occurred in 1887 when Dorr. E. Felt’s
US-patented key driven ‘Comptometer’ took calculating into the push button age.
This machine, too, spurred a host of imitators.

The Curta calculator was developed in 1948 and, although
costly, became popular for its portability. This purely mechanical hand-held
device could do addition, subtraction, multiplication and division. By the
early 1970s electronic pocket calculators ended manufacture of mechanical
calculators, although the Curta remains a popular collectable item.

The Curta
Calculator, resembling a pepper grinder with
numbers, is highly sought after by collectors of slide rules and similar calculating
devices. It was produced in two models:

- Type I -Eight columns of numbers
- Type II -Eleven columns of numbers

The Curta
Calculator came in a can, usually black,
two inches in diameter and four inches high. It was manufactured in
Liechtenstein (which borders Switzerland).

The
first mainframe computers, using firstly vacuum tubes and later transistors in
the logic circuits, appeared in the 1940s and 1950s. This technology was to
provide a stepping stone to the development of electronic calculators.

The
Casio Computer Company, in Japan, released the Model 14-A calculator in 1957,
which was the world's first all-electric (relatively) "compact"
calculator. It did not use electronic logic but was based on relay technology,
and was built into a desk.

Colossus was a specialised machine that basically performed
“exclusive or” (XOR) Boolean algorithms.

However, it did this using hundred of thermionic valves as
electronic on/off switches, as well as an electronic display.

The application of this technology to the world’s first
general calculating computer had to wait until 1946 and the construction of the ENIAC(Electronic Numerical Integrator
And Computer) as a completely digital artillery firing table calculator also
capable of solving "a large class of numerical problems", including
the four basic arithmetical functions.

ENIAC |

ENIAC was 1,000 times faster than electro-mechanical
computers and could hold a ten-digit decimal number in memory. But to do this
required 17,468 vacuum tubes, 7,200 crystal diodes, 1,500 relays, 70,000
resistors, 10,000 capacitors and around 5 million hand-soldered joints. It
weighed around 27 tonnes, took up 1800 square feet of floorspace and consumed
as much power as a small town. Not exactly a desktop solution.

In 1961, First electronic calculators invented: Anita MK VII
and Anita MK8. This was the world’s first
all-electronic desktop calculator and it was developed in Britain by Control
Systems Ltd., marketed under its Bell Punch and Sumlock brands.

ANITA used the same push
button key layout as the company’s mechanical comptometers, but these were the
only moving parts. All the rest was done electronically, using a mix of vacuum
and cold cathode ‘Dekatron’ counting tubes.

Nevertheless, as the only electronic desktop calculator
available, tens of thousands of ANITAs were sold worldwide up to 1964, when
three new transistorised competitors appeared; the American Friden 130 series,
the Italian IME 84, and the Sharp Compet CS10A from Japan.

Canon, Mathatronics, Olivetti,
SCM (Smith-Corona-Marchant), Sony, Toshiba, and Wang.

Four of these Beatles-era
transistorised calculators were especially significant, including Toshiba’s "Toscal" BC-1411 calculator, which was remarkable in
using an early form of Random Access Memory (RAM) built from separate circuit
boards.

The same year emerged the ELKA 22 designed by Bulgaria’s
Central Institute for Calculation Technologies and built at the Elektronika
factory in Sofia.

Built like a T-64 tank and weighing around 8 kg, this was
the first calculator in the world to include a square root function.

Cal Tech |

All electronic calculators to this point had been bulky and heavy machines, costing more than many family cars of the period.

However in 1967, Texas Instruments released their landmark
"Cal Tech" prototype,
a calculator that could add, multiply, subtract, and divide, and print results
to a paper tape while being compact enough to be held in the hand.

1970
-- The first battery-operated "hand-held" calculators are sold. Most
are too large to actually be considered "pocket calculators," but
they are far smaller than anything seen before.

In
mid-1970, Sharp begins to sell the QT-8B which, by using rechargeable
batteries, is a portable version of their desk-top QT-8.

Canon's
"Pocketronic" sales begin in the Fall of 1970 in Japan and February
1971 in the USA. Canon used Texas Instruments' ICs and thermal printer. Selling
for just under $400, the "Pocketronic" was a four function,
hand-held, printing calculator, with the only display being the printed tape
running out of the side of the machine. It looks much like the
"Cal-Tech" prototype (see 1965). The unit was rechargeable, used a
disposable tape cartridge, and weighed 1.8 lbs.

Later
that year, Sharp begins to market the EL-8, a "small" hand-holdable
calculator with four function calculating power, 8 numeric tubes for a display,
and rechargeable batteries. Redesigned from the QT-8 series, the unit is
smaller and weighs 1.7 lbs.

## No comments:

## Post a Comment