Home
14 items | 6 visits
Here are some web resources for your invention project.
Updated on 2009-05-05
Created on 2009-05-05
Category: Schools & Education
URL:
-
Machine gun - Wikipedia, the free encyclopedia
-
However, it would not be until the mid-19th century that successful machine-gun designs came into existence. The key characteristic of modern machine guns, their relatively high rate of fire and more importantly machine (automatic) loading, came with the Model 1862 Gatling gun, which was adopted by the United States Navy. These weapons were still powered by hand; however, this changed with Hiram Maxim's idea of harnessing recoil energy to power reloading in his Maxim machine gun. Dr. Gatling also experimented with electric-motor-powered models; this externally powered machine reloading has seen use in modern weapons as well. The Vandenburg and Miltrailleuse volley (organ) gun concepts have been revived partially in the early 21st century in the form of electronically controlled, multibarreled volley guns. It is important to note that what exactly constitutes a machine gun, and whether volley guns are a type of machine gun, and to what extent some earlier types of devices are considered to be like machine guns, is a matter of debate in many cases and can vary depending which language and exact definition is used.
-
-
Revolver - Wikipedia, the free encyclopedia
-
A revolver works by having several firing chambers arranged in a circle in a cylindrical block that are brought into alignment with the firing mechanism and barrel one at a time. In contrast, other repeating firearms, such as lever-action, pump-action, and semi-automatic, have a single firing chamber and a mechanism to load and extract cartridges into it. A single action revolver requires the hammer to be pulled back by hand before each shot. In contrast, in a double action revolver, squeezing the trigger can pull back the hammer to cock the gun as well as serving to release the hammer.
-
In a single action revolver, the hammer is manually cocked, usually with the thumb of the firing or supporting hand. This action advances the cylinder to the next round and locks the cylinder in place with the chamber aligned with the barrel. The trigger, when pulled, releases the hammer, which fires the round in the chamber. To fire again, the hammer must be manually cocked again. This is called "single action" because the trigger only performs a single action, of releasing the hammer. Because only a single action is performed and trigger pull is lightened, firing a revolver in this way allows most shooters to achieve greater accuracy. Additionally, the need to cock the hammer manually acts as a safety.
- 2 more annotations...
-
-
Soda fountain - Wikipedia, the free encyclopedia
-
The soda fountain was made with attempts to replicate mineral waters that bubbled up from the Earth's crust. Many civilizations believed that drinking and/or bathing in these mineral waters cured diseases, and large, profitable industries often sprang up around hot springs, such as Bath in England or the many onsen of Japan.
-
The soda fountain began in Europe but achieved its greatest success in the United States. Benjamin Silliman, a Yale chemistry professor, was among the first to introduce soda water to America.
- 3 more annotations...
-
-
Typewriter - Wikipedia, the free encyclopedia
-
In 1865, Rev. Rasmus Malling-Hansen of Denmark invented the Hansen Writing Ball, which went into commercial production in 1870 and was the first commercially sold typewriter. It was a success in Europe and was reported as being used in offices in London as late as 1909.[6] In addition, Malling-Hansen used a solenoid escapement to return the carriage on some of his models and was a responsible candidate for the first "electric" typewriter. From the book Hvem er Skrivekuglens Opfinder?, written by Malling-Hansen's daughter, Johanne Agerskov, we know that, in 1865, Malling-Hansen made a porcelain model of the keyboard of his writing ball and experimented with different placements of the letters to achieve the fastest writing speed. Malling-Hansen placed the letters on short pistons that went directly through the ball and down to the paper. This, together with placement of the letters so that the fastest writing fingers struck the most frequently used letters, made the Hansen Writing Ball the first typewriter to produce text substantially faster than a person could write by hand.
Malling-Hansen developed his typewriter further through the 1870s and 1880s and made many improvements, but the writing head remained the same. On the first model of the writing ball from 1870, the paper was attached to a cylinder inside a wooden box. In 1874, the cylinder was replaced by a carriage, moving beneath the writing head. Then, in 1875, the well-known tall model was patented and it was the first of the writing balls that worked without electricity. Malling-Hansen attended the world exhibitions in Vienna in 1873 and Paris in 1878. At both exhibitions, he received the first-prize medals for his invention.[7][8][9]
-
The first typewriter to be commercially successful was invented in 1867 by Christopher Sholes,[1] Carlos Glidden and Samuel W. Soule in Milwaukee, Wisconsin. Sholes soon disowned the machine and refused to use or even to recommend it.[1] The patent (US 79,265) was sold for $12,000 to Densmore and Yost, who made an agreement with E. Remington and Sons (then famous as a manufacturer of sewing machines) to commercialize the machine as the Sholes and Glidden Type-Writer, which was the origin of the term typewriter. Remington started production of its first typewriter on March 1, 1873, in Ilion, New York. It had a QWERTY keyboard layout, which because of the machine's success slowly was adopted by other typewriter manufacturers.
-
1 - 14 of 14
Showing 20▼ items per page
List Comments
(0)
List Info
Sponsored Links
Ads by Google
Matt Gillingham's Public Lists (18)
- 19th century inventions
- Bill Becomes Law
- Cold Fusion
- Constitutional Issues
- Cyberbullying
- History of Earth and Evolution
- memoir lexiles
- Memoirs
- presidential_campaign_commercials
- presidential_election
- Probability
- Problem Solving
- races
- Seedfolks
- Shakespeare in the park
- This I Believe
- This I Believe Leads
- weather