10 Inventions by Thomas Edison (That You've Never Heard Of)

Edison was a 22-year-old telegraph operator when he received his first patent for a machine he called the electrographic vote-recorder. He was one of several inventors at the time developing methods for legislative bodies, such as the U.S. Congress, to record their votes in a more timely fashion than the time-honored voice vote system.

In Edison's vote-recorder, a voting device was connected to the clerk's desk. At the desk, the names of the legislators were embedded in metal type in two columns -- "yes" and "no." Legislators would move a switch on the device to point to either "yes" or "no," sending an electric current to the device at the clerk's desk. After voting was completed, the clerk would place a chemically treated piece of paper on top of the metal type and run a metal roller over it. The current would cause the chemicals in the paper to dissolve on the side for which the vote should be recorded. "Yes" and "no" wheels kept track of the vote totals and tabulated the results.

A friend of Edison's, another telegraph operator named Dewitt Roberts, bought an interest in his machine for $100 and tried to sell it to Washington to no avail. Congress wanted no part of any device that would increase the speed of voting -- decreasing the time for filibusters and political wheeling and dealing -- so young Edison's vote-recorder was sent to the political graveyard.

Edison invented the ancestor of the tattoo gun -- the pneumatic stencil pen. This electric pen, which Edison patented in 1876, used a rod tipped with a steel needle to perforate paper for printing purposes. It's important on its own as one of the first devices that could efficiently copy documents.

In 1891, tattoo artist Samuel O'Reilly was awarded the first patent for a tattoo machine -- a device allegedly based on Edison's stencil pen. O'Reilly apparently produced only one of the machines and that was for his own personal use -- there is no record of his marketing his device.

O'Reilly immigrated to New York City from Ireland in 1875. After he developed his tattoo machine, many sideshow and circus attractions began frequenting his shop at No. 11 Chatham Square. The machine was much quicker than hand tattooing, and the performers thought it gave cleaner results. After O'Reilly's death in 1908, a student took up his trade and machine and worked at Coney Island until the 1950s.

Probably the biggest financial failure of Edison's career was the magnetic ore-separator. The idea, which Edison's laboratory experimented with during the 1880s and 1890s, was to use magnets to separate iron ore from unusable lower-grade ores. This would mean that abandoned mines could be profitable once again through the extraction of iron from sand at the sites. At the time, iron ore prices had risen to unprecedented heights.

Edison's laboratory was preoccupied with developing a magnetic ore-separator and putting it to practical use. He acquired rights to 145 abandoned mines and set up a pilot project at the Ogden mine in New Jersey. Edison poured money into the project, gradually selling most of his interest in the General Electric Company to pay for his work. But the engineering problems were never worked out and the price of iron ore fell, leading Edison to finally abandon his precious separator.

All sorts of issues arise when you're doing something that has never been done before -- like running electrical services to businesses and residences. You need a way to measure how much customers consume so you'll know what to bill them.

Edison solved this problem by patenting the Webermeter in 1881. The Webermeter contained two or four electrolytic cells with zinc at both electrodes and a zinc sulfate solution. The zinc transferred from one electrode to the other at a set rate as electricity was used. The meter reader removed the electrolytic cells at each reading for weighing, replacing them with new ones.

Another Edison invention came about from the laboratory's work with glass vacuum tubes while developing the incandescent light bulb. A development, we should add, that is not solely Edison's. Many others were involved in the research and labor of the light bulb production -- but Edison got the much-sought after patents.

But getting back to our story. In 1881, Edison filed for a patent for a method to preserve fruits, vegetables or other organic substances in a glass vessel. The vessel was filled with the items to be preserved, and then all the air was sucked from it with an air pump. The vessel tube was sealed with another piece of glass.

Another food-related invention, wax paper, is often attributed to Edison, but it was invented in France in 1851 when Edison was just a child. Edison did use wax paper in his sound recording work, which might be where the story originated.

Edison believed cars would be powered by electricity, and in 1899 he began to develop an alkaline storage battery that would power them. He was on to something: In 1900, about 28 percent of the more than 4,000 cars produced in America did run on electricity [source: PBS]. His goal was to create a battery that would run for 100 miles (161 kilometers) without recharging. Edison gave up the project after about 10 years because the ready abundance of gasoline made the electric car a moot point.

But Edison's work wasn't in vain -- storage batteries became his most profitable invention and were used in miners' headlamps, railroad signals and marine buoys. His friend Henry Ford also used Edison's batteries in his Model Ts.

Not satisfied with having improved the average American's life with electric lights, movies and phonographs, the Wizard of Menlo Park decided in the early part of the 20th century to abolish city slums and get every working man's family into sturdy, fire-proof homes that could be built inexpensively on a mass scale. And what would those homes be made of? Why, concrete, of course, using materials from the Edison Portland Cement company. Edison, recalling his own working-class upbringing, said he would take no profit if the venture succeeded.

Edison's plan was to pour the concrete into large, wooden molds the size and shape of a house, let it cure, remove the framework and -- voila! A concrete house, with decorative molding, plumbing pipes, even a bathtub, molded right in. Edison said these dwellings would sell for around $1,200, about one-third the price of a regularly constructed house at the time.

But while Edison Portland Cement was used in a lot of structures around New York City during the building boom of the early 1900s, the concrete houses never caught on. The molds and equipment needed to make the homes required a huge financial investment that few builders were able to make. Image was another problem -- not many families wanted the social stigma of moving to a house that was touted as getting people out of the slums. One other factor: Some people thought the homes were ugly. While the company did build a few concrete houses around New Jersey -- some still standing today -- Edison's vision of concrete neighborhoods never took [source: Onion].

And what did Edison expect you to furnish your concrete home with? Keep reading to find out why the inventor wouldn't have been a good interior designer.

Why should a young couple go into debt to purchase furniture that will last only a few decades? Edison proposed that for half the money, they could obtain a house full of concrete furniture that would endure for eternity. Made with air-impregnated foam to keep the weight at only one-and-a-half times that of wooden furniture, Edison's line of concrete furnishings would be sanded and smoothed into a mirror-like finish or stained to look like wood grain. He claimed he could furnish an entire house for less than $200.

In 1911, Edison's company molded a piano, bathtub and cabinets that could house Edison's phonographs. They shipped the phonograph cabinets around the country as a publicity stunt, and Edison affixed stickers on the packaging, asking the shippers to please handle them roughly. The cabinets were to be unveiled in New York City at the annual cement industry show, but Edison didn't show up, and the cabinets weren't heard of again. Suspicions are that the cabinets didn't survive the trip.

Once Edison had patented his phonograph, he began to devise ways to use it. One idea, first mentioned in a laboratory note in 1877, but not patented until 1890, was to miniaturize the phonograph and insert it into a doll or other toy, giving the formerly inarticulate plaything a voice of its own. The phonograph was enclosed in a tin casing that composed the doll's chest, then pre-made arms and legs were attached, along with a bisque head made in Germany. The talking dollies sold for about $10. Little girls sat in factory stalls and recorded the songs and nursery rhymes that were inscribed on the wax cylinders for the phonographs to play.

Unfortunately, the idea of a talking toy was far ahead of the technology needed to execute it. Sound recording was in its infancy, and the cracklings and hissing on early records were more disturbing when they were supposed to be the voices of sweet-faced dolls.

"The voices of the little monsters are exceeding unpleasant to hear," one customer complained. Most dolls did not play at all, or the voice was too faint to be heard. The doll's fragile form did not protect the delicate mechanism from shaking and jolts, and its purpose as a child's toy almost guaranteed the phonograph for dolls would not get the delicate care it required.

Taking the idea of the telephone and the telegraph a bit further, Edison announced in October of 1920 that he was working on a machine to open the lines of communication with the spirit world. In the aftermath of World War I, spiritualism was undergoing a revival, and many people hoped science could provide a means to access the souls of the recently deceased. The inventor, himself an agnostic who admitted he had no idea if a spirit world even existed, spoke of his quest in several magazines and explained to The New York Times that his machine would measure what he described as the life units that scatter through the universe after death.

Edison corresponded with British inventor Sir William Crookes, who claimed to have captured images on "spirit photographs." These photos allegedly encouraged Edison, but he never introduced any machine that he said could communicate with the dead, and after his own death in 1931, no machine was found. Many people believe he was just playing a joke on the reporters he'd talked to about his "spirit phone."

Some people claimed that at a séance in 1941, Edison's spirit told the participants that three of his assistants possessed the plans. The machine was reportedly then built, but did not work. Later, at another séance, Edison supposedly suggested some improvements. Inventor J. Gilbert Wright was present and worked on the machine until his own death in 1959, but, as far as we know, never used it to contact spirits.