Historical
Ladders are ancient tools and technology. A ladder is featured in a Mesolithic rock painting that is at least 10,000 years old, depicted in the Spider Caves in Valencia, Spain. The painting depicts two humans using a ladder to reach a wild honeybee nest to harvest honey. The ladder is depicted as long and flexible, possibly made out of some sort of grass.
Variations
Rigid ladders
Rigid ladders are available in many forms, such as:
- Accommodation ladder, portable steps down the side of a ship for boarding.
- Assault ladder, used in siege warfare to assist in climbing walls and crossing moats.
- Attic ladder, pulled down from the ceiling to allow access to an attic or loft.
- Bridge ladder, a ladder laid horizontally to act as a passage between two points separated by a drop.
- Boarding ladder, a ladder used to climb onto a vehicle. May be rigid or flexible, also boarding step(s), and swim ladder.
- Cat ladder (US chicken ladder), a lightweight ladder frame used on steep roofs to prevent workers from sliding.
- Christmas tree ladder, a type of boarding ladder for divers which has a single central rail and is open at the sides to allow the diver to climb the ladder while wearing swimfins.
- Counterbalanced ladder, a fixed ladder with a lower sliding part. A system of counterweights is used to let the lower sliding part descend gently when released.
- Extension ladder or "telescopic ladder", a fixed ladder divided into two or more lengths for more convenient storage; the lengths can be slid together for storage or slid apart to expand the length of the ladder; a pulley system may be fitted so that the ladder can be easily extended by an operator on the ground then locked in place using the dogs and pawls. 65 ft, 50 ft and some 35 ft extension ladders for fire service use "bangor poles", "tormentor poles" or "stay poles" to help raise, pivot, steady, extend, place, retract and lower them due to the heavy weight.
- Fixed ladder, two side members joined by several rungs; affixed to structure with no moving parts.
- Folding ladder, a ladder in the step ladder style with one or more (usually no more than three) one-way hinges. Ideal for use on uneven ground (e.g. stairs), as a trestle or when fully extended a Fixed ladder. Some variations feature a central one-way hinge with extensible locking legs.
- Hook ladder or pompier ladder, a rigid ladder with a hook at the top to grip a windowsill; used by firefighters.
- Mobile Safety Steps are self-supporting structures that have wheels or castors making them easy to move. They sometimes have a small upper platform and a hand rail to assist in moving up and down the steps.
- Orchard ladder, a three legged step ladder with the third leg made so that it can be inserted between tree branches for fruit picking.
- Platform ladder, a step ladder with a large platform area and a top handrail for the user to hold while working on the platform.
- Retractable ladder, a ladder that looks like a drainpipe but can be deployed instantly when required.
- Roof ladder, a rigid ladder with a large hook at the top to grip the ridge of a pitched roof.
- Sectional ladder, also known as a builder's ladder, has sections that come apart and are interchangeable so that any number of sections can be connected.
- Step ladder, a self-supporting portable ladder hinged in the middle to form an inverted V, with stays to keep the two halves at a fixed angle. Step ladders have flat steps and a hinged back.
- Swim ladder, a ladder used by swimmers to get out of the water, often on boats.
- Telescoping ladder, commonly used to refer to a hybrid between a step ladder and an extension ladder with 360-degree hinges; has three parts and can be taken apart to form two step ladders; e.g. Little Giant.
- Trestle ladder, an "A-Frame"-style ladder with a telescoping center section.
- Turntable ladder, an extension ladder fitted to rotating platform on top of a fire truck.
- Vertically rising ladder, designed to climb high points and facilitate suspending at said high points.
- X-deck ladder, a US patented ladder design that is a combination ladder and scaffold.
Rigid ladders were originally made of wood, but in the 20th century aluminium became more common because of its lighter weight. Ladders with fiberglass stiles are used for working on or near overhead electrical wires, because fiberglass is an electrical insulator. Henry Quackenbush patented the extension ladder in 1867.
If you want to read more, go here: https://en.wikipedia.org/wiki/Ladder
- 3/4 cup (1-1/2 sticks) butter, divided
- 1 cup onion, finely chopped
- 1 tablespoon minced garlic
- 1 (15-ounce) can tomato sauce
- 2 cups heavy cream
- 3 teaspoons garam masala, divided
- 1 teaspoon ground turmeric
- 1 teaspoon salt
- 1/2 teaspoon cayenne pepper
- 2 pounds boneless, skinless chicken breasts, cut into 1/2-inch chunks
- 1 tablespoon vegetable oil
- 2 1/2 cups cooked white rice, warmed
- Preheat oven to 375º.
- In a medium skillet over medium heat, melt 1/2 stick butter. Add onion and cook 8 minutes, stirring occasionally. Stir in garlic and continue to cook for 2 to 4 minutes or until onions are golden.
- Meanwhile, in a large pot over medium heat, melt remaining 1 stick butter. Add tomato sauce, heavy cream, 2 teaspoons garam masala, the turmeric, salt, and cayenne pepper; bring to a low boil. Reduce heat to low, and continue to cook for 15 minutes.
- In a large bowl, toss chicken with oil and remaining 1 teaspoon garam masala, and place on baking sheet. Bake 12 to 15 minutes or until no longer pink in center.
- Stir onion and chicken into sauce mixture and simmer 5 minutes. Serve butter chicken over hot rice.
HOW TO OBSERVE
- Volunteering for your local veteran organization
- Donate to a veteran service organization
- Adopt a Medal of Honor grave site
- Fly the U.S. flag at your home or business
- Visit the Tomb of the Unknown Soldier
- Visit local memorial sites
NATIONAL MEDAL OF HONOR DAY HISTORY
Q. Have any women received the Medal of Honor?
A. Yes. Following the American Civil War, President Andrew Jackson presented Dr. Mary Edwards Walker with the Medal of Honor for her volunteer work with the Union Army, often going behind enemy lines to care for civilians.
Q. Has any U.S. president received the Medal of Honor?
A. Yes, but only one. Theodore Roosevelt received the honor for his services during the Spanish American War. It was awarded to Roosevelt posthumously by President Bill Clinton in 2001.
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