The History of the Light Bulb
More than 150 years ago, inventors began working on a bright idea that would have a dramatic impact on how we use energy in our homes and offices. This invention changed the way we design buildings, increased the length of the average workday and jumpstarted new businesses. It also led to new energy breakthroughs -- from power plants and electric transmission lines to home appliances and electric motors.
Like all great inventions, the lamp globes can’t be credited to one inventor. It was a series of small improvements on the ideas of previous inventors that have led to the light bulbs we use in our homes today.
INCANDESCENT BULBS LIGHT THE WAY
Long before Thomas Edison patented -- first in 1879 and then a year later in 1880 -- and began commercializing his incandescent light bulb, British inventors were demonstrating that electric light was possible with the arc lamp. In 1835, the first constant electric light was demonstrated, and for the next 40 years, scientists around the world worked on the incandescent lamp, tinkering with the filament (the part of the bulb that produces light when heated by an electrical current) and the bulb’s atmosphere (whether air is vacuumed out of the bulb or it is filled with an inert gas to prevent the filament from oxidizing and burning out). These early bulbs had extremely short lifespans, were too expensive to produce or used too much energy.
When Edison and his researchers at Menlo Park came onto the lighting scene, they focused on improving the filament -- first testing carbon, then platinum, before finally returning to a carbon filament. By October 1879, Edison’s team had produced a light bulb with a carbonized filament of uncoated cotton thread that could last for 14.5 hours. They continued to experiment with the filament until settling on one made from bamboo that gave Edison’s lamps a lifetime of up to 1,200 hours-- this filament became the standard for the Edison bulb for the next 10 years. Edison also made other improvements to the light bulb, including creating a better vacuum pump to fully remove the air from the bulb and developing the Edison screw (what is now the standard socket fittings for light bulbs).
(Historical footnote: One can’t talk about the history of the light bulb without mentioning William Sawyer and Albon Man, who received a U.S. patent for the incandescent lamp, and Joseph Swan, who patented his light bulb in England. There was debate on whether Edison’s light bulb patents infringed on these other inventors’ patents. Eventually Edison’s U.S. lighting company merged with the Thomson-Houston Electric Company -- the company making incandescent bulbs under the Sawyer-Man patent -- to form General Electric, and Edison’s English lighting company merged with Joseph Swan’s company to form Ediswan in England.)
What makes Edison’s contribution to electric lighting so extraordinary is that he didn’t stop with improving the bulb -- he developed a whole suite of inventions that made the use of light bulbs practical. Edison modeled his lighting technology on the existing gas lighting system. In 1882 with the Holborn Viaduct in London, he demonstrated that electricity could be distributed from a centrally located generator through a series of wires and tubes (also called conduits). Simultaneously, he focused on improving the generation of electricity, developing the first commercial power utility called the Pearl Street Station in lower Manhattan. And to track how much electricity each customer was using, Edison developed the first electric meter.
While Edison was working on the whole lighting system, other inventors were continuing to make small advances, improving the filament manufacturing process and the efficiency of the bulb. The next big change in the incandescent bulb came with the invention of the tungsten filament by European inventorsin 1904. These new tungsten filament bulbs lasted longer and had a brighter light compared to the carbon filament bulbs. In 1913, Irving Langmuir figured out that placing an inert gas like nitrogen inside the bulb doubled its efficiency. Scientists continued to make improvements over the next 40 years that reduced the cost and increased the efficiency of the incandescent bulb. But by the 1950s, researchers still had only figured out how to convert about 10 percent of the energy the incandescent bulb used into light and began to focus their energy on other lighting solutions.
The children's globe is a necessary teaching aid in the teaching of geography in primary and secondary schools. It is often used to explain the following:
1. the earth
Understand the causes of the alternation of day and night and the change of seasons
Analyze the impact of the movement of the earth on the climate
2. Distribution characteristics of latitude and longitude lines
Shape direction length
Know the role of graticule
3. The world's land and sea
Understand the positional relationship between the seven continents and the four oceans and the latitude zone they are in
Know the location of the six major sectors
Recognize the topographic features of major terrain areas and major continents
Find the position of the date line
Astronomy Globe
Astronomy globe simulates the movement of the sunshine area on the earth's surface caused by the earth's rotation and revolution. This movement produces astronomical information-day, night, sunrise, sunset, solar terms (seasons), polar day area, polar night area, location of direct sun points, local time, universal time, time difference, etc. This information is what people need to know in their daily lives. In the past, people used clocks, globes, or the integrated use of maps and calendars to obtain some information, but the time of sunrise and sunset in different areas, the length of day and night that change with solar terms (seasons), and the angle of sunlight are still unavailable. They can only be measured or asked. observatory.
The astronomical globe gives this information, so you can know it in a hotel, home or office. The solar terms (seasons) were given by the calendar in the past. The astronomical globe not only gives the solar terms (seasons) but also the sunrise and sunset times and the length of day and night for each region, as well as the latitude of the point where the sun shines. The polar day and polar night regions were only mentioned when learning geography knowledge or traveling to high latitude regions in summer. The astronomical globe can provide information about the polar day and polar night regions at any time, which has great practical significance for tourism. People know the conditions of the polar day and polar night areas before traveling to high latitude areas. In the past, the direct sun point was only experienced by people between the Tropic of Cancer. There is also a measuring building from the sun to the Tropic of Cancer in Guangzhou. With the astronomical globe, people can experience the meaning of the direct sun point through it.
The globe is a model of the earth. Although it cannot represent various geographical things and phenomena in detail like a map, nor can it fully reflect the actual situation of the earth, it can avoid errors and distortions in length, direction, area or shape on the map, and can help us Clarify many related concepts of the earth and obtain the concept of the main body of the earth.
Demonstrate the deflection force of the earth's rotation
In order to observe the deflection force of the earth’s rotation, we can use a globe to make the earth’s axis perpendicular to the ground plane and move the north pole of the globe upward. The meridian flows to low latitudes and leaves ink marks. Then you turn the globe from west to east, and then drop one or two drops of blue ink at the original place at high latitudes, and you will find that the direction of the blue ink flow has changed to the right compared to the direction of the original red ink flow. Turn the globe to the side, with the South Pole facing up, and perform two demonstrations in the same way. Comparing observations, the trajectory of the blue ink flow is deflected to the left compared to the trajectory of the red ink flow.
Then place the globe at rest and flat, the axis of the earth is parallel to the horizon, drop one or two drops of red ink on a certain point on the equator, and find that the red ink flows along the line of the equator; then drop one or two drops of blue ink at the origin and rotate the globe, It was found that the flow orbit of the blue ink was consistent with that of the red ink, indicating that its flow orbit was not affected by the rotation of the earth. Therefore, it can be proved that under the influence of the deflection force of the geostrophic force, the law of deflection of horizontally moving objects is as follows: the northern hemisphere deviates to the right, the southern half of the day deviates to the left, and there is no deflection on the equator.
Demonstrate the day and night change
Use an electric light or a bright flashlight to represent the sun so that it is on the same plane as the sphere of the globe. The globe rotates from west to east around the earth's axis (the north end of the earth's axis points to true north). The period of the earth's rotation (a 360° revolution) is a sidereal day, which is 23 hours, 56 minutes and 4 seconds. When the globe rotates from west to east, the globe rotates counterclockwise when viewed from the north pole; the globe rotates clockwise when viewed from the south pole; the globe rotates from west to east when viewed from the equator. These three expressions are consistent. Since the earth (instrument) is an opaque sphere, the sun (electric light or a strong flashlight) can only illuminate half of the earth at the same time, that is, the sun is day and the sun is night. The hemisphere illuminated by the sun (electric light or a strong flashlight) is called the day hemisphere, and the hemisphere illuminated in the middle of the night is called the night hemisphere. The dividing line (two) between the two balls is combined into a circle, called the twilight line (circle). When the earth (instrument) continuously rotates from west to east, we will find that the direct sun's point sweeps from east to west, and the twilight circle also moves regularly from east to west, so the day and night on the earth are constantly changing. . The globe keeps turning from west to east, which can demonstrate the regular day and night changes on the earth.
In addition to providing globes, we also provide various globe accessories.