Historical Science & Technology

What Time Is It? Water o’ Clock

A water clock, or clepsydra, is a unique style of timepiece that measures time via the regulated flow of liquid (usually water, hence the name) into or out of a vessel (called inflow and outflow, respectively). Along with the sundial and the hourglass, the water clock is among the oldest known time-measuring devices.

Hail Clepsydra

The oldest surviving physical evidence of a water clock dates to roughly 1400 BCE. This water clock was used in the Temple of Amen-Re during the reign of Pharaoh Amenhotep III in Ancient Egypt. However, an inscription on the tomb of Egyptian court official Amenemhet identifying him as the inventor dates back at least two more centuries.

Um... not quite...

Um… not quite…

Even older evidence suggests that water clocks were used in astronomical calculations during the Old Babylonian period (circa 2000-1600 BCE). No physical examples from this period still remain, but records written on clay tablets have survived. The Babylonians measured time using temporal hours, which meant that, as seasons changed, the length of an hour fluctuated. As such, the amount of water that had to pass through these water clocks to mark each “hour” changed, as well.

Pints of Persia

Historical records of water clocks dating to 328 BCE describe the ancient Persians in what is now Iran using them to ensure the just and exact distribution of water from local wells for irrigation purposes. Water clocks were also used to calculate the holy days of pre-Islamic religions, such as the equinoxes and solstices.

A typical Persian water clock of this vintage consisted of a large pot full of water and a bowl with a small hole in its center. The bowl would be placed on top of the water, where it would start to slowly fill with water. Once full, it would sink into the pot. It was then retrieved and emptied, and the process would be repeated as necessary. Typically, the “manager” of the water clock would tally the number of cycles by placing a small stone in an unrelated jar for each time the bowl sank.

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Historical Science & Technology, Technology, World-Changing Inventions

A Brief History of Industrial Machining

The term “machining” refers to any of a number of processes by which raw material is cut, ground, or otherwise mechanically/physically transformed into a desired final shape via controlled material removal. Sometimes referred to as “subtractive machining,” the basic process has been used since the first caveman sharpened a stick on a rock to create a makeshift spear. In the more modern sense, machining has been used extensively since the 18th century CE and is a major part of manufacturing and other industrial processes.

The Meaning of Machining

Prior to Ye Olde Industrial Revolution, a “machinist” was a dude who built and/or repaired machines, work that was done almost exclusively by hand. By the middle of the 19th century, industry all around the world was revolting and the definition of “machinist” had become more akin to what we think of now—someone who machines material into an end product, part, or component via turning, drilling, boring, sawing, shaping, etc. Early machine tools such as lathes, drill presses, and milling machines helped launch the first wave of modern machinists.

The lathe dates back to ancient Egypt, but did not become mechanically powered—and thus far more powerful and useful—until the Industrial Revolution. The earliest lathes can be traced back to roughly 1300 BCE. These lathes were operated by a two-person team, one of whom turned the wooden workpiece with a length of rope, while the other cut shapes into the wood with sharp tools. Pedal power replaced hand-operated lathes by the Middle Ages. The first true machine lathe was a horizontal boring machine installed at the British Royal Arsenal in 1772. The horse-powered machine was used to manufacture cannons used in the Revolutionary War. So, ultimately, not a huge success.

An early mechanical lathe (circa 1919) from a Canadian metalworking factory.

An early mechanical lathe (circa 1919) from a Canadian metalworking factory.

Very early humanoids invented the first drills circa 35,000 BCE. (What highs and lows humanity has experienced in the millennia since!) These first rudimentary drills were little more than pointed sticks that were rubbed between the palms—flint points were sometimes attached. Bow- or strap-drills were developed approximately 10,000 years ago, and were primarily used to create fire. Augers were first used to drill (or dig) large holes in the heyday of the Roman Empire. The drill press was derived from the bow-drill, and early models were windmill- or water wheel-powered. The invention of the electric motor in the late 1800s led to the invention of the electric drill and drill press, early versions of which are not all that much different than those we use today.

Machining Today

While some aspects of machining equipment have remained largely the same, there are other devices that would have been wholly unimaginable to Industrial Revolutionaries. Fully-automated, CNC-powered machining centers can now do the work of a dozen or more men in a fraction of the time, and even have the capability change out their own tools if, for example, a drill bit breaks mid-operation. New machining methods, like electrical discharge machining, make full use of technologies that were barely even conceived of in the 1800s. Even the machine enclosures used today, with soundproofing, temperature control, air-cleaning HVAC systems, and other advanced features, are technological marvels by Industrial Revolution standards.

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Historical Science & Technology, Pseudoscience

The Baghdad Battery

These days, batteries are everywhere and in everything. You’ve probably got one in your pocket right now, in fact (in your phone). The origin of modern batteries can be traced back to good ol’ Big Ben Franklin in the 1700s, but the alkaline batteries that were the standard for decades did not appear until 1899. Less than two decades later, lithium batteries had been developed; lithium-ion batteries took another 60 years to appear, with rechargeables not far behind.

But way, way back when, in the Parthian period (circa 250 BCE to 224 CE), the first-ever battery was invented. Or was it?

Scroll Storage or Power Source?

The “Baghdad Battery” consists of three components: a ceramic pot, a copper tube, and an iron rod. Though its true purpose remains unclear, the most widely accepted explanation of this disparate trio is that they were used collectively to store sacred scrolls—wrap the scrolls around the rod, but the rod into the tube, and stow the tube in the pot.

A modern, commercially-available version of the Baghdad Battery.

A modern, commercially-available version of the Baghdad Battery.

However, upon its initial discovery, it was speculated that these three pieces could be combined to create a galvanic cell; that is, a battery.

Some folks speculate that, with the addition of wine, lemon juice, grape juice, or vinegar to serve as acidic electrolyte, the copper and iron materials could function as electrodes and produce an electrical current. Researchers, particularly German painter and naturalist Wilhelm “Big Willie” König, noted that a high number of objects from ancient Iraq (whence the “battery” originated) were plated with very thin layers of gold. These researchers suggest that the Baghdad Battery was used to perform an early type of electroplating.


Though at least two attempts to duplicate the Baghdad Battery’s supposed electrical potential have proved successful, the genuine artifact has since been debunked as a possible power source. Firstly, an iron-copper-electrolyte junction produces gas and, along with it, bubbles; these bubbles would create insulation around the electrode; this insulation would increase with ongoing use, making the battery progressively less effective. Secondly, even in a perfect setup, the voltage generated by an iron-copper-electrolyte cell of this size would be far lower than that required for electroplating.

König later determined that the “electroplated” items he had studied were, in fact, fire-gilded with mercury.

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Historical Science & Technology, War: What Is It Good For? (Absolutely Nothin'!)

Hillforts of Iron Age Britain

A hillfort (or hill fort [or hill-fort]) is pretty much just what it sounds like—a fort built into the top of a hill. Generally, hillforts featured an open central area where one or more buildings stood, with multiple ramparts of earth, stone, and/or wood surrounding the central area and proceeding down the hill to exploit the topography and gain a tactical advantage over would-be attackers. Beyond these ramparts was often a ditch or moat.

Historical evidence shows that these structures were first developed in the Late Bronze Age/Early Iron Age, and a number of these ancient hillforts still exist to this day. While the structures were common throughout Europe, here we will be focusing on the hillforts of Britain.

The Why, The How, The Whatnot

There are a number of theories relating to the emergence of hillforts in Britain. Some speculate that they were forts in the truest sense—military installations intended to keep invaders from mainland Europe at bay. Others argue that they may have been built by those same invaders to establish a stronghold on the island.

Modern view of Maiden Castle, built in the Iron Age near what is now Dorchester.

Modern view of Maiden Castle, built in the Iron Age near what is now Dorchester.

Still others suggest that the hillforts may have been constructed in response to social changes in the country, brought on by the increased use of iron. (It was the Iron Age, after all.) Because Britain’s prominent iron ore deposits were located in different regions than the tin and copper ore used to make bronze, trade patterns shifted greatly, and power shifted along with them.

Though a good number of hillforts were built during the Bronze Age, most of them were erected between 700 BCE and 43 CE (which coincides with the Roman conquest of Britain). Iron Age hillforts utilizes both natural and manmade defenses.

The ancient Britons built four main types of hillforts: contour, promontory, hill-slope, and plateau. Contour hillforts cut off the upper portion of the hill from the ground below with ramparts that followed the natural contours of the hill itself. Promontory hillforts limited the approach of outsiders through the use of natural features such as cliffs, steep slopes, rivers, etc. Hill-slope hillforts do not enclose the entire hilltop like contour forts do; instead, they are situated on the slope of one side of the hill, with the crest overlooking the structure. Plateau hillforts were built on the flat, level expanses of plateaus.

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Historical Science & Technology, War: What Is It Good For? (Absolutely Nothin'!)

Historic Maritime Inventions of Ancient Africa

An 8,000 year old canoe, carved from African mahogany, was discovered in Nigeria in 1987 CE. The third oldest remaining example of a canoe in the world, and the oldest ever found on the African continent, it is noted for a “stylistic sophistication” that suggests that the practice of building canoe extends far farther back in time than the 7th century BCE. What other significant seafaring inventions have come out of Africa in centuries or millennia past?

I’m On A (Very, Very Old) Boat

The oldest Egyptian boat yet discovered is dated to roughly 3000 BCE. Evidence suggests that ancient Egyptians were assembling wooden planks into ships’ hulls at least 5,000 years ago, with woven straps used to lash the planks together and reeds or grass stuffed into the seams to seal them. A fleet of 14 boats constructed in this manner was discovered by Egyptologist David “Big Dave” O’Connor near the burial site of Pharaoh Khasekhemwy. The largest of these boats was over 75 feet long.

Other, not quite as old Egyptian vessels were built using treenails (wooden dowels), with pitch used to caulk the seams. A 140-plus foot ship, constructed in this manner and dated to roughly 2500 BCE, was discovered in a sealed pit at the foot of the Great Pyramid of Giza. Other surviving examples of ancient Egyptian boats used mortise and tenon joints to join planks.

These and other types of boats were used to establish a trade route across the sea between northern Africa and India. Additional evidence suggests north African boats sailing to Greece and beyond.

King Abubakari’s Armada (featuring Herman Menderchuk)

In the 14th Century CE, King Abubakari II of the Mali Empire amassed a fleet of several hundred ships. These ships, frequently sighted along the western coast of Africa, communicated with each other via drums. The sheer number of boats, and their rather impressive construction, has led many scholars to surmise that Malian seamen may very well have reached what is now North America several hundred years before Christopher Columbus.

war canoe

In addition to their mighty armada, ancient West African peoples also made extensive use of canoes and similar small vessels throughout the inland waterways of the area. Mostly carved and/or dug out from a single huge log (usually a silk cotton tree), these canoes were used for both transportation and warfare. Most were propelled by good ol’ paddles, with sails used where possible. The largest of the war-canoes measured up to 80 feet long and could carry 100 men. Tribes in the Niger Delta and what is now Guinea were especially well-known for their canoe crafting capabilities.

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