Foundations of Mechanics: Part 2?

Welcome to this blog series designed to guide you on an exciting journey through the realm of mechanics. This area of physics is pivotal in shaping our grasp of the physical Universe, ranging from the basic machines of ancient times to the intricate research methods of biomechanics today. In this series, I'll delve into the core principles of mechanics, charting its historical development from the brilliant revelations of Aristotle and Archimedes, through the ground-breaking ideas of Newton, to its crucial role in modern biomechanics research. Each post will enhance your understanding of essential concepts and link those notions to innovative uses that are changing our world, especially in biomechanics. Join me as I explore the mechanics underlying everything from the equilibrium of forces to the movement of bodies.

As I pointed out in Part 1, mechanics operates independently of human intervention. However, this raises an intriguing question: When did humans first start using and studying mechanics? Regrettably, the exact time of this isn't known. Humans have engaged with mechanics from the start of our existence, yet where is the proof? Observing our biological relatives, like chimpanzees, provides some insights. They naturally grasp mechanics well. Watching them swing from tree to tree clearly shows they understand concepts like momentum and the force of gravity, even if they don't have names for them. They can also use simple stone tools to crack open things like nuts. However, we can only partially take this observation to be scientific proof of humans using mechanics.

Stone clubs represent the earliest mechanical devices created by humans to appear in archaeological findings. In 2010, an international research team found animal bones in Ethiopia's Lower Awash Valley. These bones had marks made by stone tools, and the findings are dated back to 3.4 million years ago. Suppose we accept that humans crafted these tools. In that case, these marks are our oldest proof of humans employing mechanical techniques. Numerous other ancient stone weapons have been found, some dating as far back as 500,000 BCE.

Evidence suggests considerable time passed before humans created more advanced tools. Some evidence was recently found in Sibudu Cave, located on the east coast of South Africa, suggesting that people during the Stone Age were utilising arrowheads as components of bows and arrows as far back as 60,000 BCE. Regrettably, this method didn't become widespread; it vanished and only emerged 20,000 years later. Nevertheless, the technique of shaping stones through mechanical processes marked a substantial advancement for humanity. If you want to understand the difficulty of this task, try shaping a sharp edge on a flint piece by striking it with another rock. Thus, although we're still determining the exact techniques they employed to form arrowheads, we do possess evidence that humans engaged in what we today would describe as 'experimental' mechanics at least 60,000 years ago.

One more instance of people employing mechanical techniques can be observed in ancient cave paintings, like those found in the Cave of El Castillo in northern Spain, around 40,000 years old, and others in Chauvet, France, from approximately 35,000 years ago. It appears that the creators of these incredible artworks might have used mechanical tools to prepare their pigments, possibly by crushing them into a fine powder using stone tools. Nevertheless, we can only confirm this with a certain degree of certainty.

The first clear signs that people were using mechanical principles for things other than creating tools or weapons emerged slightly later. Bones discovered in France were identified as originating from the Aurignacian culture, dating back to around 32,000 BCE, which clearly showed the use of a lunar calendar. Furthermore, markings in France's well-known Lascaux cave paintings are lunar calendars. These calendars are dated to about 13,000 BCE. This is much stronger proof that humans were exploring mechanics. To create a calendar, you need to understand the movements of celestial bodies, essentially studying mechanics. Therefore, it is evident that humans were investigating mechanical concepts a very long time ago.

By chance, Lascaux is a genuinely fascinating cave. It was first found in the region of South Central France on September 12, 1940, by a group of four young people. Inside the cave are close to two thousand paintings, with some believed to be around 17,300 years old. The cave welcomed visitors starting in 1948, but by 1963, it had to be shut down because of harm brought on by carbon dioxide emissions from the people visiting. In an unexpected turn of events, the local people chose to construct an identical copy of two of the caves. This project proved to be quite a problematic building task, yet it was indeed completed, and Lascaux II was opened for public viewing in 1983. Sadly, the original cave has kept on deteriorating. However, Lascaux II remains functional. Moreover, a mobile exhibition known as Lascaux III was launched in 2012, and in 2016, another replica called Lascaux IV was inaugurated on the hillside that faces Montignac. At the start of the tour inside the replica cave, guests are given a detailed explanation of the methods used to construct Lascaux II. This explanation itself is an exciting lesson in structural mechanics (we will discuss this further in a later instalment of the blog series). Although visitors today cannot enter the original Lascaux cave, the tour of this duplicate cave is still awe-inspiring.

Excavations that started in the middle of the nineteenth century in what is now Iraq have uncovered compelling proof that the Mesopotamians were making astronomical observations as far back as the eighteenth century BCE. To date, over 500,000 cuneiform tablets have been found at sites such as Sippar, located just southwest of Baghdad, and many of these tablets were utilised to track the movements of celestial bodies. These findings suggest that the Mesopotamians were the earliest civilisation on the planet to undertake systematic scientific research, with their observations of the stars being fundamentally based on mechanical principles.

At the close of the Pleistocene era, approximately 10,000 BCE, it is likely that humans were actively exploring and utilising the principles of mechanics. Indeed, several surviving carvings demonstrate efforts to develop solar calendars around the time when the final ice age concluded. This is significant not only because solar calendars provide a higher accuracy compared to lunar calendars but also because they necessitate more sophisticated mechanical knowledge. Consequently, this evidence supports the notion that mechanics has been a profoundly established and complex field in human activities.

You would be correct in thinking that mechanics is indeed the oldest of the sciences, dating back to the initial attempts by humans to understand the movements of stars and planets. Ancient stone monuments like Stonehenge, Avebury, and Beltany, along with many other large stone structures across Western Europe, align with the movements of the Earth about the Sun. This alignment shows that people were observing the Moon's path and the Earth's over 5,000 years ago. At Stonehenge, located on the Salisbury Plain in southern England, the Sun directly aligns with the central line of the henge during the summer solstice. These ancient societies were not just creating stone structures that served as calendars but also checking these structures for precision. This activity reflects their use of mechanics as a way to apply scientific methods.

Stonehenge is an ancient site that was first used around 8,000 BCE. Scientists have found wooden pieces in the surrounding earth mound, which suggests that the original structure might have been made of wood. Early builders probably realised they needed a more robust material than wood to create long-lasting structures. Thus, they opted for stone. Today, we see that nearly all the ancient buildings that have survived are made of stone. However, the close placement of the tall vertical stones at Stonehenge shows a limitation of stone: it isn't suitable for long horizontal beams. This is because stone has a low capacity for handling tension, the stretching force that acts on horizontal beams under weight. This tells us our ancestors knew, at least through trial and error, about the challenges of using beams, a mechanical issue that wasn't fully understood scientifically until the eighteenth century. Nowadays, we know that a horizontal stone beam under weight will experience tension at its lower side, and because stone can easily break under such stress, it is unsuitable for long horizontal spans.

There is another captivating challenge in mechanics linked to Stonehenge: how the ancient builders transported the large stones to their current location remains a mystery. The type of bluestones used at Stonehenge cannot be found within 240 km of the Salisbury Plain now, indicating that a significant human effort might have been required to move them there. Nonetheless, some archaeologists think the Irish glacier carried the stones closer to the site during the last ice age. The puzzle of how Stonehenge was constructed remains a deeply fascinating topic, as those who have watched documentaries about the site can attest. Regrettably, no surviving records detail how these ancient builders achieved such an impressive task, leaving us only with guesses.

No matter where they originated, moving and then setting up the stones would have been a huge task in ancient engineering. It has been proposed that the building process required particular technological abilities, including understanding the lever principle and using transport tools like boats, wheels, or rolling frameworks, which were probably already in use in different societies long before the creation of large stone calendars. Yet, there is still no agreement on the exact methods used. What we can definitely say, though, is that knowledge of mechanics was essential for the construction methods applied.

Avebury, located in southwestern England, is home to Europe's biggest stone circle. This historical site was established around 2,600 BCE, making it one of the earliest star-based calendars known on the planet. Throughout the British Isles, there are over a thousand stone circles scattered across the landscape. Many of these circles were left unused when the Iron Age started, which was around 800 BCE in these regions. This abandonment might have been influenced by the Celtic invasions of Western Europe during that period, which resulted in the original inhabitants being driven out by the Celts, who had superior weapons and armour crafted with the use of mechanics.

Research indicates that the stone structures we see today were preceded by earlier, more fragile structures that likely existed before the start of the Holocene period, which began over 12,000 years ago as the ice age ended. However, in the context of the Earth's entire history, we possess only limited solid evidence to demonstrate that humans have studied mechanics for more than a few tens of thousands of years. The available evidence does show that their interest in mechanics was not purely out of curiosity. It appears they pursued this knowledge primarily as a vital tool for survival. Understanding the seasonal shifts by observing the movement of celestial bodies and creating weapons were essential practices for enduring the harsh conditions of early environments. By the start of the third millennium BCE, stone structures used for calendars were quite common in Western Europe, as shown by the many still standing today. However, there is little evidence of the specific methods used to create these lasting monuments to our ancestors' inventiveness.

The contributions from regions like the Middle East, India, and possibly China seem more significant than traditional history books suggest. Over time, archaeologists have been uncovering increasing amounts of evidence to support this. Take the Sumerians, for instance. Around 5,000 years ago, they developed the sexagesimal (base-60) numbering system, which continues to influence our lives today. We use this system when we divide an hour into 60 minutes and a minute into 60 seconds. Similarly, we split a circle into 360 degrees. You may wonder why we adhere to such a system when humans typically have 10 fingers and 10 toes, which makes a base-10 system more intuitive. The choice is based on practicality, although it's unclear why the Sumerians, and later the Babylonians, initially adopted this system. However, once established, it influenced many aspects of our current numerical and timekeeping systems. Notably, 360 is the smallest number divisible by each number from 2 to 10, as well as by 24, the number of hours in a day as chosen by humans. This choice may have links to the number of constellations, which is 12 - a figure also invented by humans - but this is not confirmed. We do know that the concept of a 24-hour day has been in use for a long time, evidenced by its mention in the tomb of Egyptian pharaoh Amenhotep I, dating back to 1500 BCE.

The decision to use a 24-hour day is probably not accidental, considering the Earth rotates about 15° each hour. It's also possible that the use of 360° was influenced by the Moon's orbit around the Earth, which takes roughly 29.5 days. In the past, this was often simplified to 30 days in ancient calendars, and they chose to have 12 months in a year. This might have been done to align with the number of constellations, leading to a year that is around 360 days long. Such a setup is crucial for navigation, especially when observing the stars and planets, and it's clear that all these factors are connected to basic physical principles.

Up to now, researchers and historians have yet to clearly identify who first came up with the crucial concept of the number zero. It's known that the Egyptians used a numeric system based on ten as far back as 1740 BCE, represented by hieroglyphs, but the exact function of this system needs to be clarified. Some writers believe that the Babylonians might have known about zero, but it is more likely that the Greeks were the ones who developed it. However, the Greeks chose not to use zero, which ultimately led to its adoption by the Indians. The Greeks had a strong dislike for what they called irrational numbers, whereas the Babylonians managed these numbers without much trouble. Devotees of Pythagoras used his famous theorem on a triangle where each side was one unit long. This calculation resulted in an unsettling number for the hypotenuse of the triangle. Even though they proved this number was irrational, they were not pleased with this finding. In contrast, the Babylonians efficiently handled these enigmatic numbers, often rounding them off for everyday use. Understanding these mathematical concepts is essential for mechanics because measuring motion requires measuring distances.

The Babylonians, following in the footsteps of their predecessors, the Sumerians, were also highly skilled in the field of construction. In Ur, around 2,500 BCE, they built a ziggurat (like a giant, stepped cake made of bricks) that featured weep holes for adequate drainage. Remarkably, two levels of this temple still stand today. These levels include arches, which were used two thousand years before the Romans started to widely apply this architectural feature. Scientists and mathematicians in India were examining the skies at roughly the same period. Archaeologists think that India was one of the earliest places where modern humans lived after they moved out of Africa. Therefore, it's likely not surprising that Indians were among the first scientists to explore mechanics.

It's not easy to determine precisely how the first advancements in mechanics changed our world. However, what is obvious from the archaeological evidence is that around 95% of all early inventions were lost over time because of poor communication. Stone tools might have been created and recreated repeatedly in various places around the world. Eventually, this technology stabilised and was used widely by people everywhere. Other mechanical inventions faced similar issues, with gaps and breaks in how they were used across different areas and times. Therefore, even though the records from those times are incomplete and the information we have isn't definitive, mechanics likely had a notable impact on the development of early humans.

Even later, these advancements significantly impacted the earliest cultures on Earth, and the technology started to spread through images and written documents. The task of gathering some of this knowledge, adding to it, and forming the first organised scientific theories on Earth, including the study of mechanics, would fall to the Greeks. However, before delving into the achievements of the Greeks, it's important to give due respect to the Egyptians. Although they may not have been as scientifically advanced as their northern neighbours, they were definitely competent.

From a young age, the mysterious charm of ancient Egypt has held my attention, weaving stories of its gods and pharaohs into the core of my imagination. My interest grew intensely after watching the 1994 film 'Stargate', which combined science fiction with ancient Egyptian mythology. This film took me to a world where history merged with futuristic possibilities. It broadened my view and enhanced my appreciation for the intricate history that ancient Egypt presents. The monuments, hieroglyphs, and legends all keep my enthusiasm alive for delving deeper into this ancient civilisation.

Why does Egypt capture our attention so strongly? There are several key reasons. To begin, the Egyptian Empire was the most enduring of any ancient culture, stretching from around 3,800 BCE to 31 BCE, ending with the suicide of Cleopatra, the final pharaoh. Secondly, we can see far more of the oldest Egyptian civilisation than we can of any other from that distant past. Thirdly, the Egyptians preserved their rulers through mummification and burial in tombs, which opened a unique view into their lives. Lastly, the Egyptians recorded their history on their temple walls. When the Egyptian hieroglyphs were finally deciphered in the nineteenth century, the once-concealed stories of their formidable empire became available for everyone to explore and understand. Until the 1800s, following Napoleon's unsuccessful attempt to take over Egypt (I will return to this point), Egypt was largely isolated from Western countries. It was considered a mysterious and perilous destination for most people from the West, primarily because of the threat of deadly illnesses. It was pretty likely that anyone travelling to Egypt from the West would not return to their native country.

Everything changed when Napoleon's scientists spent three years in Egypt, starting in 1798, and shared their discoveries. Their reports amazed people in the West, leading to a constant stream of visitors to Egypt and the continuous removal of Egyptian treasures. Nowadays, while the influx of visitors still occurs when there is no civil unrest, the export of treasures has thankfully decreased remarkably due to stringent measures imposed by the Egyptian government.

To keep things simple, let me touch briefly on Egyptian history. Experts in archaeology have discovered that there was once a large lake in the middle of the Sahara Desert. It wasn't very long ago, perhaps around seven or eight thousand years, that this lake dried up. This happened partly because of changes in the climate but also because of the movement of the Earth's crust. Specifically, two tectonic plates are pushing against each other, with one plate sliding over the other in the Mediterranean Sea area. This movement created the Alps mountains and caused the ancient city of Alexandria to sink under the sea, now at the bottom of the harbour in today's Alexandria. Similarly, this geological activity is indirectly responsible for the sinking of Venice. All these events are related to the movements of tectonic plates.

When the lake located in the middle of the Sahara became dry, the native people who lived there had no choice but to leave and find new homes. A large number of these people travelled east, along the Mediterranean coast, to the rich and fertile area of the Nile delta. This migration led to a significant increase in the population there about 7,000 years ago. This surge in population resulted in a meeting and clashing of two distinct cultures: the Upper Nile and the Lower Nile. Eventually, these two cultures were brought together under the rule of a ruler, possibly named Narmer, around 3,800 BCE. The evidence of Narmer's unification can be observed in a small sculpture, the Palette of Narmer, housed in the New Grand Egyptian Museum in Giza. It's regarded as one of the oldest and most significant artefacts created by humans, holding tremendous archaeological value. The majority of scholars believe that Narmer might have been the first pharaoh, meaning a ruler of both the upper and lower parts of the Nile. We understand that he was definitely a pharaoh because images on both the front and back of the Palette of Narmer show him wearing the crowns that symbolise the two regions. His period of rule possibly started the era known as The Old Kingdom.

The ancient Egyptians held a strong belief in an afterlife. They took extraordinary measures to ensure their pharaohs would continue to experience luxury even after death, so they constructed intricate burial tombs. Some regular people also received burial tombs, but their wealth and social status determined their design and size. As the wealthiest and most significant figure in society, the pharaoh received the most elaborate tomb. However, there was a major issue. The tombs were built using the most accessible material available at the time in Egypt – mud – which was formed into bricks. Regrettably, a few centuries later, it became clear to everyone (particularly the pharaohs who came after) that mud bricks were unsuitable. The harsh desert climate caused the bricks, and thus the brick tombs, to erode, seriously compromising the intended luxurious afterlife conditions of the deceased pharaohs. Consequently, the use of mud bricks did not meet the grand expectations of the pharaohs.

Enter the pyramids! Now, no one can say for sure when the Egyptians started to extract stone, or indeed, identify who first began this practice in the world, but it is acknowledged that the Egyptians commenced crafting giant, sculpted statues several millennia ago. They had access to tough granite (notably at Swenet, now known as Aswan, and at other sites) and softer limestone in various locations along the Nile. They also had the opportunity to work with stones of medium hardness, such as marble. It was only a short time before they started decorating monuments with statues made of stone, and it was a brief step from there to constructing entire buildings out of stone. Eventually, they devised the concept of creating the Pharaoh's mastaba tomb entirely from stone. This structure consisted of a single layer built above an underground burial complex. By that period, the Egyptians had become acutely aware that their own people were plundering the Pharaohs' tombs. Therefore, stone was chosen because it provided protection against both thievery and the elements.

Around 2,630 BCE, Pharaoh Djoser, who was ruling during the Old Kingdom period, came up with the concept of adding another level to his flat-topped tomb, known as a mastaba. Following this, he added a third level, then a fourth, and eventually a fifth, possibly because he lived longer than he initially thought he would. As a result, the first Egyptian pyramid came into existence, although it should be noted that there are some earlier, simpler pyramidal structures made from unshaped stones in Caral, Peru. The pyramid Djoser built today is referred to as a step pyramid, characterised by its layered design, with each layer smaller than the one below it. This innovative design was the work of a man named Imhotep, who is notable for being the first engineer recorded by name in history. Imhotep's creation evidently made a significant impact at the time, as he was eventually worshipped as a deity by the Egyptians for thousands of years after that, an extraordinary feat for an engineer.

Djoser's tomb was seen as very remarkable during its time, with Egypt experiencing a period of considerable wealth. This economic prosperity enabled subsequent pharaohs to afford the construction of their own grand tombs. Within less than a century, the era of constructing massive pyramids was underway. By the fifth dynasty of the Old Kingdom, the most prolific pyramid builder in history emerged as the pharaoh. His name was Snefru, and he is credited with constructing at least three major pyramids, though some suggest he may have built up to six. The three pyramids that remain today are in differing states of preservation. One of these, located far out in the desert at Meidum, is known as the Meidum Pyramid. It has largely crumbled due to flaws in the engineering of its structure. While this might seem like a failure, it's important to recognise that the pyramid still exists despite its collapse. How many of us can claim to have created something that will endure for 5,000 years?

Snefru believed he could improve, so he began building another pyramid at Dashur, a short distance south of Saqqara. This second pyramid encountered structural issues as well, and they altered the angle of the pyramid halfway through its construction (probably to reduce the stress on the structure). Today, this is known as The Bent Pyramid. A lot of the original limestone coating remains on the pyramid, giving us an idea of how the others might have looked long ago. More than that, the striking simplicity of this grand structure standing alone in the desert leaves an impression on visitors. And it has been there for nearly 5,000 years. Next time you decide to create something, think about designing it to last 5,000 years. If you manage to do that, people might remember your name 5,000 years from now.

So Snefru eventually succeeded. This random method of constructing pyramids was probably the biggest and most expensive example of figuring out structural design through trial and error in history, even when considering the era of gothic cathedrals. The idea of building such enormous structures by trial and error today would be unthinkable to engineers. For one thing, their companies would face financial ruin by the second attempt. But that was the situation with the limited knowledge of mechanics that people had less than 5,000 years ago.

There's another point to make about these pyramids. During Snefru's time, his engineers didn't know how to construct an arch. So, they used a clever method to create chambers within the Red Pyramid. We now refer to this technique as a corbel arch. This method involves cutting long granite stones and layering them slightly over each other as they are stacked upwards. Using this building method, they managed to construct chambers over 12 metres high inside the pyramids. This technique is a very clever use of basic engineering principles. It's likely that many workers ended their days with aching backs from the hard labour!

The Eiffel Tower, constructed in 1889, stands approximately 320 metres (1,050 feet) high. Since its completion over a century ago, more than 100 buildings taller than it have been erected around the world. Today, we live in an era where there's an expectation for humans to continually construct larger and taller buildings at an increasing pace. However, the past did not always embrace such ambitious architectural feats. Until the construction of Lincoln Cathedral in 1300, the title of the tallest structure made by humans was held by the Great Pyramid of Khufu at Giza. Constructed around 2,550 BCE, it reached about 150 metres, nearly half as tall as the Eiffel Tower.

According to ancient Greek scholars, the tale tells us that the first renowned scientist was a Greek called Thales. He existed in the sixth century BCE. At one point during his life, he travelled from his home in Miletos to view the pyramids. His reputation was so great that the Pharaoh personally invited him to the palace. During this visit, the Pharaoh asked Thales if he could work out the height of this ancient and magnificent structure. This is how ancient the Great Pyramid is. It is so ancient that even the pharaohs from the later Egyptian periods regarded it as a relic from antiquity!

Thales tackled the issue by applying mathematical techniques. He positioned a pole known as a gnomon (an early version of a sundial) into the Earth and took note of the pole's height and the length of the shadow it cast. Following this, he measured the shadow that the Great Pyramid threw. By using the concept of similar triangles, he worked out the height of the Great Pyramid. This might be among the earliest surviving instances of trigonometry being used on the planet, a branch of mathematics crucial for the study of mechanics.

From the measurements taken by Thales, we can calculate the volume of the Great Pyramid of Khufu. Knowing the volume of a common stone block used in its construction, it's been calculated that around 2.3 million stone blocks (each weighing about 2,500 kg) were required to finish the structure. Yet, the method used to build this enormous pyramid is still unknown today.

Even though archaeologists have yet to find out exactly how the Great Pyramids were built, there are some interesting hints. For instance, at the Temple of Karnak in Luxor, archaeological evidence suggests mud brick ramps might have been used to lift some of the stones. Moreover, there are signs that stones might have been dragged on wooden sledges and that they could have been pushed up the ramps on rollers. However, using rollers comes with many issues, particularly on slopes. The rollers tend to roll out from under the load towards the lower or back side, which can be hazardous for the workers below. Additionally, suppose the rollers are not perfectly cylindrical (having the same shape and size throughout) and uniform. In that case, they create extra problems that can increase the risk for the workers.

Many modern engineers have come up with different ways to build things, and one of these methods might be the one that was actually used. For instance, some people think that the stones were fixed with a disk at each end and rolled up ramps. This method has an unexpected advantage: the rope is tied around the stones instead of the disks. Depending on how big the disk is compared to the stones, the rope unwinds a bit quicker than the disks turn. This makes it easier for people to pull on the disk. This presents an interesting issue in the field of mechanics. Another suggestion, presented by French architect Jean-Pierre Houdin, suggests that a series of internal spiral ramps were built first, and the remaining blocks were pulled up inside this structure. The design of the Great Pyramid supports this idea. However, in truth, the methods used to build the Egyptian pyramids are still a big puzzle even now.

In recent years, many studies have been carried out which suggest that one or more of the previously mentioned building methods were used. The estimates of how many workers were needed to match the evidence found in recent archaeological excavations at the site. Using the mathematics of mechanics, researchers have figured out that 10,000 workers could set the pyramid stones in place within about 13 years. However, this number needs to be increased to include the cutting and moving of the stones. Additionally, extra staff would have been necessary to supply food and other essentials to the workers. If the work for quarrying, transporting, and supporting is as demanding as the stone setting, then the total number of workers required multiplies by four, resulting in an estimated 51 years for the project if 10,000 workers are involved. On the other hand, 20,000 workers could finish in about 25 years and 40,000 workers in about 13 years. This provides a basic idea of the workforce needed for the Great Pyramid of Khufu, matching well with more precise estimates reported recently. Several other accurate estimates have been made using this method, aligning closely with the rough approximation presented here.

We're not sure about the exact methods used to build the Great Pyramid, but the principles of mechanics suggest that it was indeed possible to make such a structure using a large number of workers and the technology that existed during Khufu's time. By around 2,500 BCE, the era of building great pyramids had ended. The main reason seems to be an economic downturn, leaving insufficient resources for future pharaohs to employ 40,000 people for 13 years to construct more huge pyramids. Additionally, there was a more philosophical reason for stopping: the pyramids were not effective. Despite their size and secretive design, tomb robbers broke in and stole valuable items within a few years. As a result, the pharaohs had to look for new methods to ensure they would be comfortable in the afterlife. However, the Great Pyramid of Khufu remained the tallest structure on Earth until 1,300 AD, and it is still one of the biggest structures ever built in the world.

The ancient Egyptians made substantial contributions to the field of mechanics, mainly through their pioneering construction methods and tools, which still influence our understanding of basic mechanical principles today. The building of the pyramids is the most famous example of how the ancient Egyptians excelled in using leverage. However, the shaduf, a less well-known manually operated device for raising water, is another instance of their skill in using leverage, an essential device for irrigation. The Egyptians' employment of ramps to shift large blocks during the construction of pyramids shows an early use of the principles of inclined planes to lessen the force required to raise weights, another key idea in mechanics. Additionally, they created various tools that demonstrate mechanical principles, such as the plumb bob, to ensure vertical alignment and the square level for accuracy in construction. Their innovations included the introduction of copper and bronze tools, which enabled more effective construction techniques. Their selection of materials and construction techniques also demonstrates an understanding of stress distribution and material strength, which are critical concepts in mechanical engineering.

Come back next time for Part 2, where we will examine the further development of mechanics in ancient Greece.

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