A pencil (/ˈpɛnsəl/ ⓘ) is a writing or drawing implement with a solid pigment core in a protective casing that reduces the risk of core breakage, and keeps it from marking the user's hand.
Pencils create marks by physical abrasion, leaving a trail of solid core material that adheres to a sheet of paper or other surface. They are distinct from pens, which dispense liquid or gel ink onto the marked surface.
Most pencil cores are made of graphite powder mixed with a clay binder. Graphite pencils (traditionally known as "lead pencils") produce grey or black marks that are easily erased, but otherwise resistant to moisture, most solvents, ultraviolet radiation and natural aging. Other types of pencil cores, such as those of charcoal, are mainly used for drawing and sketching. Coloured pencils are sometimes used by teachers or editors to correct submitted texts, but are typically regarded as art supplies, especially those with cores made from wax-based binders that tend to smear when erasers are applied to them. Grease pencils have a softer, oily core that can leave marks on smooth surfaces such as glass or porcelain.
The most common pencil casing is thin wood, usually hexagonal in section, but sometimes cylindrical or triangular, permanently bonded to the core. Casings may be of other materials, such as plastic or paper. To use the pencil, the casing must be carved or peeled off to expose the working end of the core as a sharp point. Mechanical pencils have more elaborate casings which are not bonded to the core; instead, they support separate, mobile pigment cores that can be extended or retracted (usually through the casing's tip) as needed. These casings can be reloaded with new cores (usually graphite) as the previous ones are exhausted.
As a technique for drawing, the closest predecessor to the pencil was silverpoint or leadpoint until in 1565 (some sources say as early as 1500), a large deposit of graphite was discovered on the approach to Grey Knotts from the hamlet of Seathwaite in Borrowdale parish, Cumbria, England. This particular deposit of graphite was extremely pure and solid, and it could easily be sawn into sticks. It remains the only large-scale deposit of graphite ever found in this solid form. Chemistry was in its infancy and the substance was thought to be a form of lead.[citation needed] Consequently, it was called plumbago (Latin for "lead ore"). Because the pencil core is still referred to as "lead", or "a lead", many people have the misconception that the graphite in the pencil is lead, and the black core of pencils is still referred to as lead, even though it never contained the element lead. The words for pencil in German (Bleistift), Irish (peann luaidhe), Arabic (قلم رصاص qalam raṣāṣ), and some other languages literally mean lead pen.
United States
American colonists imported pencils from Europe until after the American Revolution. Benjamin Franklin advertised pencils for sale in his Pennsylvania Gazette in 1729, and George Washington used a three-inch pencil when he surveyed the Ohio Country in 1762. William Munroe, a cabinetmaker in Concord, Massachusetts, made the first American wood pencils in 1812. This was not the only pencil-making occurring in Concord. According to Henry Petroski, transcendentalist philosopher Henry David Thoreau discovered how to make a good pencil out of inferior graphite using clay as the binder; this invention was prompted by his father's pencil factory in Concord, which employed graphite found in New Hampshire in 1821 by Charles Dunbar.
By the end of the 19th century, over 240,000 pencils were used each day in the US. The favoured timber for pencils was Red Cedar as it was aromatic and did not splinter when sharpened. In the early 20th century supplies of Red Cedar were dwindling so that pencil manufacturers were forced to recycle the wood from cedar fences and barns to maintain supply.
Eraser attachment
On March 30, 1858, Hymen Lipman received the first patent for attaching an eraser to the end of a pencil. In 1862, Lipman sold his patent to Joseph Reckendorfer for $100,000, who went on to sue pencil manufacturer Faber-Castell for infringement. In Reckendorfer v. Faber (1875), the Supreme Court of the United States ruled against Reckendorfer, declaring the patent invalid.
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- SERVES
- 8
- COOK TIME
- 25 Min
Lookin' for an easy casserole recipe with ground beef? Well, look no further, 'cause Veggie Beef Casserole is a real crowd-pleaser! Like the name says, you're in for some veggie and beef goodness topped with a bit of cheese. This casserole mixes up in a snap and will vanish just as quickly!
- 8 ounces uncooked elbow macaroni
- 1 1/4 pound ground round
- 1 (16-ounce) bag frozen mixed vegetables, thawed
- 2 (10-3/4-ounce) cans cream of mushroom soup, undiluted
- 1 cup milk
- 1 teaspoon onion powder
- 1/2 teaspoon salt
- 1/2 teaspoon black pepper
- 2 teaspoons Worcestershire sauce
- 1/2 cup (2 ounces) shredded sharp Cheddar cheese
- Cook macaroni according to package directions. Drain and set aside.
- Preheat oven to 375º. Coat a 9-x13-inch baking dish with cooking spray.
- Cook beef in a large skillet over medium-high heat, stirring until it crumbles and is no longer pink; drain and return to skillet. Add the remaining ingredients, except the cheese, and heat until bubbly.
- Add the macaroni to the mixture and mix well. Spoon mixture into baking dish. Sprinkle with cheese. Bake, uncovered, 20-25 minutes or until heated through.
1944 – George Lucas, American director
1984 – Mark Zuckerberg, American computer programmer and internet entrepreneur, co-founder of Facebook
Alexander P. Ashbourne patented the first biscuit cutter in 1875.
HOW TO OBSERVE
- Make biscuit breakfast sandwiches with eggs and cheese.
- Serve biscuits with your favorite soup. It’s better than dumplings!
- Use biscuit dough to make pizza crust. Partially bake the dough before adding toppings.
- Warm biscuits with butter and jelly satisfy every time.
- Serve biscuits with pork chops, pork loins, or pulled pork.
- BBQ and biscuits hit the spot, too. They soak up the juices quite well.
- Whenever you have fresh fish, serve homemade biscuits. Catfish and biscuits are particularly delicious.
- Who likes tomato sandwiches during the summer? When fresh tomatoes ripen on the vine, slice them up while they’re warm. Add a little bit of mayonnaise and sprinkle of salt and sandwich them between two warm biscuits.
- Don’t forget dessert. Biscuits make an excellent base for strawberry shortcake. Just add a little sugar to your dough to sweeten it. You’ll make up the rest of the sweetness with the strawberries and whipped cream.
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