Landin’s Computing Machine Explained – Everything You Need to Know

Early computers are amongst some of the most fascinating inventions around, and they were instrumental in changing the way that we were able to complete tasks such as calculating and even programming. Peter Landin was a British computer scientist who invented such a machine. He is also credited with creating the SECD machine, the first abstract machine for a functional programming language, and the ISWIM programming language. However, Landin didn’t just invent computer-related devices. He also owned other patents for devices such as cash registers and a phonograph.

Read on to learn more about Peter Landin and his inventions, including details of his early career, his numerous patents, how his computing machine worked, and why it was so historically significant.

Facts about Landin’s Computing Machine

• The Landin’s Computing Machine is a slide-chain adder with seven digital settings that you may manipulate with a pin or pencil.
• Landin’s Computing Machine is a well-designed and well-constructed gadget with a solid and sturdy build.
• It was invented in 1890 by Peter J. Landin (Mar. 9, 1858–Jan. 24, 1940) from Minneapolis, Minnesota, who took out a US patent №482312 on 6th September 1892.

Landin’s Computing Machine: History

The invention of Peter Landin relates to the improvements in computing machines, with the object that the machine of that class would be of simple construction and operation and by which arithmetical computations may be made and results indicated upon the machines.

Peter John Landin was a British computer scientist who lived from 5 June 1930 to 3 June 2009. He was the first to recognize that people might use lambda calculus to describe a programming language, which is crucial for developing functional and denotational semantics.

Peter Landin holds several other US patents, including the ones for cash registers and recorders (patent numbers 482014, 526400, 526401, and 526402); a phonograph (No1422453); and a motion picture film (No1234046), among others. Landin worked for the Walker family, which built one of the largest forest products corporations in the US, thus a highly successful American business family. Fletcher Loren Walker (1872-1962) witnesses the first co-holder of the other patents assigned to his father, Thomas B. Walker.

Landin’s Computing Machine: How It Worked

The Landin’s Computing Machine, also known as Landin’s computer, has the following description and working procedure.

A shaft is mounted in the case, and a series of ratchet wheels are divided into ten spaces that form the 10 teeth or notches by the wheel that you can rotate. A series of bars or slides extend longitudinally of the machine. The top forward portions of these slides are provided with a series of openings or notches suitable for the reception of the stylus, i.e., a pin, pencil, finger of the operator, or other suitable devices for operating the slide. Each slide is provided with nine of these openings. The rear end of each slide extends over one of the wheels, and the other side comes in contact with the wheel.

It has a serrated or toothed portion corresponding with the wheel’s notches, number, and size. As the slide is moved through the machine, you can rotate the wheel. Casting’s front portion is cut away over the slides’ ends, and the edge of this cutaway portion forms a stop against which the operating pin is brought as the slides are moved and limits the movement of each of the said slides.

A suitable spring, secured to a portion of the frame, is attached to each slide to retract after moving it to operate the ratchet wheel. Each end of the wheel has a spring-stop, which is arranged to fall behind the notches in the said wheel and prevent it from receding or turning backward.

Disks are fastened to the shaft by splining between the wheels. A portion of the outer circumference of the disk is cut away. Each disk has a lug/projection, i.e., made of smaller diameter, compared to the wheel and is securely fastened to or made part of the said wheels, except for the one at the extreme right, which is located in a recess in the side of the wheels.

The stylus is put into the upper section’s toothed slides and pulled down to the stop, which advances the register by the appropriate number of places. The slides remain in their final position, allowing the value input to be read back straight above the stop for verification. When the left-hand lever is released, the slides return to their original position. If no checking is necessary, the lever can be locked down to provide an immediate return.

It’s a well-designed and constructed product with a sturdy and dependable build. The weight of the Landin’s Computing Machine is 750 grams, and the dimensions for the Landin’s Computing Machine is 60W x 205D x 32H, all in millimeters.

Landin’s Computing Machine: Historical Significance

The gadget was produced by Peter John Landin’s firm, Landin Computer Co., Minneapolis, from 1891 to 1895. Later on, Landin’s Computing Machine was renamed the Rapid Computer Adding Machine by Rapid Computer Co. he cost of the Rapid Computer Adding Machine was $25 around the turn of the century. Schubert & Salzer of Chemnitz, Germany, also had been producing a significantly modified version of the device under the name Comptator since 1909. The manufacture was shifted to Hans Sabielny, Dresden, Germany, in 1922, and the Comptator was again a tremendous hit on the global market.

Landin was born in Sheffield and attended King Edward VII School before graduating from Cambridge University’s Clare College. He worked as Christopher Strachey’s assistant in London from 1960 to 1964, while the latter was an independent computer consultant. The majority of Landin’s work was published at this time and during his brief stints at Univac and the Massachusetts Institute of Technology before joining the Queen Mary University of London. As stated in the prologue to the textbook Programming from First Principles, his efforts were constructing the computer science department at Queen Mary College, developing courses, and instructing students during the 1970s and 1980s.

As a member of the International Federation for Information Processing (IFIP), IFIP Working Group 2.1 on Algorithmic Languages and Calculi specifies, maintains, and supports the programming languages ALGOL 60 and ALGOL 68 Landin was involved with international standards in programming and informatics.

Landin is credited for creating the SECD machine, the first abstract machine for a functional programming language, and the ISWIM programming language, introducing the Landin off-side rule and coining the phrase syntactic sugar. As seen in Miranda, Haskell, Python, and F#, the off-side law permits bounding scope declaration using white spaces (using the light syntax).

After his essential publication “The next 700 programming languages”, another phrase coined by Landin is “The next 700…” The number “700” was picked when Landin read in the ACM Journal that there were already 700 programming languages in use. The paper opens as “… now… 1,700 distinct programming languages are employed to ‘talk’ in over 700 application fields”.