The light-emitting semiconductor material determines the LED's color, so the number of colors is infinite. As indicated by its full name â Light Emitting Diode â an LED is a diode that emits light. A diode is a device that allows current to flow in only one direction. Almost any two conductive materials will form a diode when placed in contact with each other â with a single p-n semiconductor junction between them.
For other uses, see Texas Longhorn (disambiguation) and Longhorn (disambiguation). The Texas Longhorn is a breed of cattle known for its characteristic horns, which can extend to over 1.8 m (5.9 ft) tip to tip for bulls, and 2.1 m (6.9 ft) tip to tip for steers and exceptional cows.
The heyday of the long drive was short. By the early 1870s, rail lines reached Texas so the cattle could be shipped directly to the slaughterhouses. Ranchers then began to allow cattle to graze on the open range near rail heads.But even this did not last. calf bought for $5 in Southern Texas might sell for $60 in Chicago. The problem was, of course, getting the cattle to market. In 1867, Joseph McCoy tracked a path known as the Chisholm Trail from Texas to Abilene, Kansas. The Texas cowboys drove the cattle the entire distance â 1500 miles.