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A phonograph is a device used to record and reproduce sound. The first phonograph was created by Thomas Edison in 1877, and the design was later improved by Alexander Graham Bell. In the first phonographs (also called gramophones) sound vibrations were engraved onto wax cylinders as grooves on the surface of the cylinder. Then the cylinder would be rotated, and a needle moved through the groves. The grooves caused the needle to vibrate, and the needle vibrations were amplified back into sound. By the second decade of the 1900s the wax cylinders had been replaced by discs or records, and the phonographs began to be referred to as “record players” and later “turntables”. By the 1980s the use of records and record players declined as a result of the introduction of cassettes and compact disks, and later digital music, but they are still used in niche markets and valued by collectors. In the video below, you can see a Victrola wind-up phonograph in operation. This phonograph is housed in the North Lee County Historical Society Museum in Fort Madison, Iowa. This brand of phonograph was made by the Victor Talking Machine Company, which in 1929 became RCA Victor. The Victrola features the famous logo of a dog listening to a phonograph with the caption “His Master’s Voice”.
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In the video below you can check out the murder mittens in action! The term “murder mittens” is a popular name for the paws of cats. Cats are predators and their paws are very well adapted for this function. Whereas humans have a form of locomotion that involves planting the heel of the foot (plantigrade) on the ground, cats walk on their toes or digits (digitigrade), which allows for more speed and a longer stride when running. Additionally, the paws of cats have pads that soften impacts and dampen the sounds they make when they are moving making them stealth predators. Finally, the paws of cats also have sharp retractable claws which are used to trap prey and also helps them climb. In the images below you can see science cat showing off her paws and also a mouse that she killed in our house.  The Murder Mittens  A Hapless Mouse The images of Science cat belong to the author and can only be used with permission. Seasons have had and still have a profound effect in human history, society, and psychology. The dramatic changes in the landscape that occur throughout the year have affected and are still affecting many facets of humanity from trade and warfare to the economy and the arts, and from moods to physiology. But far from the seasons being a mystery, human beings through observation and experiment have been able to determine that the cause of the seasons is the tilt in the Earth’s axis. As the Earth orbits around the sun, it does so with a tilt of 23.5 degrees with respect to the plane of its orbit. As a result of this, the Earth’s poles point towards or away from the sun at the extremes of this orbit (solstices), while during the points of the orbit at right angles to the solstices neither one pole or the other point away from the sun (equinoxes). If the Earth’s axis did not have a tilt, there would be no seasons. Imagine how different human history, society, and psychology would be!  In the images below, Science Cat demonstrates Summer, Fall, Winter and Spring with the help of an Azalea bush that grows outside of our living room window. Image from Wikipedia of the orbital relations of the Solstice, Equinox and intervening seasons by Colivine is used here under a CC0 1.0 Universal (CC0 1.0) Public Domain Dedication license. The images of Science Cat belong to the author and can only be used with permission. There was once a time when aquariums around the world consisted of a tank with vertical transparent walls through which people viewed the fish from the outside. This changed in 1985 when Kelly Tarlton’s Underwater World opened to the public in Auckland, New Zealand. This aquarium featured a revolutionary design where the tank contained a transparent viewing tunnel running through the middle, so the visitors felt they entered the tank and were surrounded by the sea creatures. This aquarium design, which now has been copied throughout the world, was conceived by New Zealand marine archeologist and diver Kelly Tarlton. Tarlton’s new aquarium design proved very popular, and within 7 weeks, the museum had 100,000 visitors. Unfortunately, Tarlton died of a heart condition at the untimely age of 47, but his museum, now renamed “SEA LIFE Kelly Tarlton's Aquarium” still lives on. The video below was shot inside an aquarium tunnel in Ripley’s Aquarium of The Smokies in Gatlinburg, Tennessee. Muskets were a firearm used for over two centuries in several armed conflicts including the Civil War. In the video below you can see a demonstration of the firing of a musket in slow motion at the fort of the Fort Frederick State Park in Maryland. The firing mechanism of the musket relies on a hammer (cock) that contains a piece of flint rock attached to its end. The hammer is pulled back into a position of tension (cocked position) thanks to a spring mechanism. When the hammer is released by operating the trigger, its flint head hits a structure called the frizzen, pushing it back and generating a spark that ignites a small amount of gunpowder under the frizzen in a space called a flash or priming pan.  In the video below, this is the first explosion that you see near the rear of the musket. Once the flash pan has ignited, the flame travels through a touch hole or vent and ignites the powder within the barrel of the musket, which results in the firing of the projectile. This is the second explosion in the video which comes out of the muzzle of the musket. You can even hear an echo of the explosion from the sound bouncing off the barracks and walls of the fort. Image of the firing mechanism of a musket by Jim Surkamp is used here under an Attribution-NonCommercial 2.0 Generic (CC BY-NC 2.0) license. A sun glitter pattern is formed when the light of the sun is reflected off the surface of ripples in the water. A smooth body of undisturbed water would produce one reflection of the sun. But the chaotic overlay of many ripples on top of each other produces numerous reflections of the disk of the sun constantly appearing, moving, and disappearing. The most recognized, photographed, and written about glitter pattern is the one produced when the light of the setting sun is reflected off an ocean or lake surface. But glitter patterns can be found anywhere there is a liquid reflecting light including Saturn’s moon, Titan, which has lakes of liquid hydrocarbons. In our planet, glitter patterns are used to produce more accurate weather forecasts. In the video below you can see a glitter pattern in slow motion on the waters of Old Farm Creek in Rockville, Maryland. Cats have a set of specialized hairs that we call whiskers and scientists call vibrissae. These hairs are longer and thicker than regular hairs and their roots are also embedded much deeper in the flesh. Whiskers are present on top of the eyes and upper lip of the animal as well as on the chin, forelegs, and ears. Each whisker is connected to a sensory structure called a proprioceptor which sends its signals to the brain, so you can think of whiskers as very sensitive tactile hairs. Whiskers allow the cat to balance its body, sense its environment, and communicate emotions. About 40% of the area of the sensory centers of the cat’s brain is involved in processing the input from whiskers! One particular thing that differentiates whiskers from other hairs is that whiskers are attached to special striated capsular muscles that can be moved voluntarily by the animal. Although people do not have whiskers, 35% of human beings have what seem to be remnants of these striated whisker muscles in their upper lips. These vestigial muscles are evolutionary remnants of the muscles that moved the whiskers of our whiskered ancestor. In the images below, you can see several views of Science Cat’s head showing her whiskers. The images belong to the author and can only be used with permission. When returning from our holidays this past year my daughter took the photo bellow. In it you can see the shadow of our plane upon a cloud surrounded by a radial rainbow. This optical phenomenon is called the “Brocken Spectre”. It occurs when the shadow of a person or an object is projected on mist or clouds. The shadow is often accompanied by a multicolored halo called a “Glory”, which is created when the light from the sun on the periphery of the shadow is diffracted by water droplets in the air.  Airplane Brocken Spectre The illusion is named after Brocken Mountain, which is the tallest mountain in the Harz Mountain Range in Germany. The foggy weather in this mountain range has led to many instances of locals witnessing and describing the Brocken Spectre throughout history, which has created a lore of fantastic tales associated with witches and devil worship. The first recorded description of the Brocken Spectre was made by the German theologician and natural scientist, Johann Silberschlag, in 1780.  Person Brocken Spectre The Brocken Spectre has been reported in many places throughout the world as well as by aviators since the early days of flying. It has been mentioned in works of literature by several authors including Charles Dickens and Lewis Carroll. Image of the airplane Brocken Spectre belongs to the author and can only be used with permission. Image of the person Brocken Spectre by Walter Baxter is used here under an Attribution-ShareAlike 2.0 Generic (CC BY-SA 2.0) license. For most people, clouds are these fluffy white things floating up in the air, which may give the impression that clouds are light, but nothing could be further from the truth. Clouds are created when water vapor condenses into minute water droplets due to changes in pressure and temperature, and water has weight. Those large cumulus clouds that you see up in the sky actually weigh hundreds of tons! The reason why clouds don’t fall is due to in part the same reason why ships built out of steel don’t sink. The density of the clouds is lower than the density of the underlying air. In other words, a given volume of air below the cloud is heavier than the same volume of air in the cloud, thus the cloud floats on this air. In cumulus clouds, this happens because as the warm air rises from the land it expands and becomes less dense. Additionally, the water droplets that make up most clouds are microscopic, and the effect of gravity on them is negligible and easily counteracted by the updraft currents within the clouds.  |
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