CALCULATOR

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.