Bifocals
Bifocals are eyeglasses with two distinct optical powers. Bifocals are commonly prescribed to people with presbyopia who also require a correction for myopia, hyperopia, and/or astigmatism.
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Ether Anesthetic
Before its development as a surgical anesthetic, ether was used throughout the history of medicine, including as a treatment for ailments such as scurvy or pulmonary inflammation. A pleasant-smelling, colorless and highly flammable liquid, ether can be vaporized into a gas that numbs pain but leaves patients conscious.
Musket
A musket is a muzzle-loaded long gun that appeared as a smoothbore weapon in the early 16th century, at first as a heavier variant of the arquebus, capable of penetrating heavy armor.
Antikythera Mechanism
The Antikythera mechanism is an ancient Greek analogue computer used to predict astronomical positions and eclipses for calendar and astrological purposes decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games.
Seed Drill
A seed drill is a device that sows the seeds for crops by positioning them in the soil and burying them to a specific depth. This ensures that seeds will be distributed evenly. The seed drill sows the seeds at the proper seeding rate and depth, ensuring that the seeds are covered by soil
Anemometer
An anemometer is a device used for measuring wind speed and direction, and is also a common weather station instrument. The term is derived from the Greek word anemos, which means wind, and is used to describe any wind speed instrument used in meteorology.
Pendulum clock
A pendulum clock is a clock that uses a pendulum, a swinging weight as its timekeeping element. From its invention in 1656 by Christiaan Huygens until the 1930s, the pendulum clock was the world's most precise timekeeper.
Electroscope
An electroscope is an early scientific instrument used to detect the presence of electric charge on a body. It detects charge by the movement of a test object due to the Coulomb electrostatic force on it. The amount of charge on an object is proportional to its voltage.
Telescope
A telescope is an optical instrument that makes distant objects appear magnified by using an arrangement of lenses or curved mirrors and lenses, or various devices used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation.The first known practical telescopes were refracting telescopes invented in the Netherlands at the beginning of the 17th century, by using glass lenses. They were used for both terrestrial applications and astronomy.
Steam Pump
a small pumping engine operated by steam. It is usually direct-acting. Savery used his invention to pump water out of a coal mine. In 1712, English engineer and blacksmith, Thomas Newcomen invented the atmospheric steam engine. The purpose of Newcomen's steam engine was also to remove water from mines.
Pressure Cooker
A pressure cooker is an airtight cooking device that cooks food quickly, thanks to the steam pressure that builds up inside. The steam also makes the food moist, which is why this device is perfect for meat stews, cheesecakes, and much more.
Sextant
A sextant is a doubly reflecting navigation instrument that measures the angular distance between two visible objects. The primary use of a sextant is to measure the angle between an astronomical object and the horizon for the purposes of celestial navigation.