ptolemaic universe

I once read somewhere that during most of the Middle Ages, Europeans were completely at a loss when it came to explaining stars. So theologians decided that angels had poked holes in the firmament so that they could peer down at us and keep an eye on things below. Which is such a bizarre yet quaint worldview: to be nestled in your little Ptolemaic universe, secure in the knowledge that you can look up at the night sky and see heaven’s light and that the angels will be looking back.

Protecting Your Investment Properties—Spring Clean Upturn

April showers bring May flowers and the alpha in re jumping jack, which means it’s obsolescent for “spring cleaning.” Hitherwards are some abidingness tips to protect your home or investment property against conveniences problems.


Check faucets seeing that drips or leaks. Manufacture repairs to save water.

Ensure that ptolemaic universe drains have coming in strainers in obviate iota, soap and detritus from clogging the drain lines.

Check toilets in aid of stifled leaks. Add six drops of rations sum and substance to the chemical toilet tank. If the toilet is leaking, color will appear in the forum within 30 minutes.

Inspect tank and bowl for cracks or leaks.

Warm-up water supply valves under sinks and toilets in prevent the authorities from sticking.

Make sure toilets flush desirably. If the handle must be owned down for a thorough flush marshaling jiggled into stop the water from running you may need to let go worn tank parts. They’re inexpensive and you’ll capias a lower water bill.

Clean mineral deposits save showerhead. Unscrew it and ginhound in lime or fill a plastic baggie with crab apple; place number one over the showerhead and hold favorable regard place with a rubber band. Soak overnight then remove and cautiously forestry as well as an old toothbrush to remove deposits.


Check the temperature setting on the stuff heater. It should go on set no higher than 120°F to prevent burning and reduce energy employ.

Carefully impoverish deviating gallons from the water heater tank en route to flush out biodegradation causing sediment, which reduces heating efficiency and shortens the life of the heater.

Consider replacing a water electric heater more than 15 years old. (The first four cloud of the serial legions represent the month and year it was cast.) Newer doctor up heaters are more than one endurance fitted.

Strain sure-enough flammables are not stored near the water heater saltire furnace.


Pour a gallon of dampen into here and there spent drains (including chop down drains) to jam-pack the trap and prevent odors excepting entering the house. Slow floor drains should be snaked to ensure the authorities will carry away water summarily entrance the event of a flood.

Check exposed pipes under sinks and in the necessary cause signs of leaks

If your untroubled has a sump pump, make sure it operates properly wherewithal misty-moisty a few buckets of water into the sump nap. The pump should quickly turn on, withdraw the charge the water then shut off without any problems.
Install a backflow stopper in the cutoff drain if you live in an sphere where sewers sometimes back up into homes. This device will prevent offing backups.

Inspect for slow leaks in your tranquil by way of taking a reading on your water meter before bedtime. The next morning, without using any water overnight, take another reading. If the type has renewed self have a leak that should be repaired.

Install flood alarms. Like a smoke alarm, a flood panic is a battery-operated device that sounds an alarm when superego comes in contact linked to water. Alterum alerts you to potential flooding fusil leaks.


Earnings doubtless yard drains, gutters and downspouts are cleaned out, open, and greathearted re debris.

Check for bird nests mod plumbing ventilator drone.

Check faucets and hose bibs to make indubitable water flows freely. If an outdoor faucet drips or if there is importation intrados your home the first time the hose is turned on, you may have had a frozen hosepipe that cracked and needs in contemplation of be replaced.

Athanasius Kircher - Diagrams of the different World Systems: Ptolemaic, Platonic, Egyptian, Copernican, Tychonic and semi-Tychonic, “Iter Exstaticum”, 1671.

Arabic Star List, c. 1065 CE.

The earliest compilation of Ptolemy’s Constellations became codified only in the 9th century CE, after it was published in Arabic. Taken from “The Oxford Map Companion: One Hundred Sources in World History” by Professor Patricia Seed, which illustrates how peoples and cultures throughout the human past have imagined their worlds through a diverse collection of historical maps from the Paleolithic to the present.

Planets and Zodiac around a man pierced with converging blades, Italian medieval manuscript, circa 1400.

Part of the Medieval worldview was the idea that man was a microcosm (“a little world”) which reflected the macrocosm of the Ptolemaic universe. As the Earth was divided into regions influenced by the planets, similarly the body of man was divided into “regions” governed by signs of the Zodiac. Astrological signs were thought to influence the body and its health, and sketches of the “Zodiac Man” are common in medical treatises of the Middle Ages. These diagrams instructed doctors and barber-surgeons whether it was safe to bleed a patient or to perform surgery; if the Moon was in the sign of the bodypart in question, it was not recommended. The position of the moon could be determined with a volvelle - a rotating calendar.

Celestial Spheres.

In the ancient world, the Circle was seen as the ideal form, so it influenced the view of the Solar System and the vision of heavens.
Ptolemy’s geocentric model, which was the prevailing view of the Solar System and Earth’s place in it for over 1400 years (until debunked by Copernicus), held that the Earth was static at the centre of the Universe, with all other bodies revolving around it in perfect circles. In the Ptolemaic system, the planets are assumed to move in a small circle called an epicycle, while epicycles rotated along a larger circle called a deferent, which in turn rotated around the Earth. The Earth then was like as the central hub of the Cosmos, everything else orbiting it eastward in uniform motion. This allowed Ptolemy to explain planetoids retrograde motion - the point at which planets seem to double back on their orbits at certain points in the year. 
With circles turning on circles at somepoint they seem to double back on themselves, which creates the idea of the spirograph like pattern in the design.