It all started with an angle

Sixty-six million years ago, an asteroid  “Chicxulub” hit Planet Earth and marked the extinction of 75% of the species. It is believed that the asteroid was roughly 10 km (6 miles) across and 60 degrees above the horizon! Sixty degrees above the horizon was particularly destructive because it allowed the asteroid to eject a large amount of aerosol and dust and maximized the number of climate-changing gases thrust into the upper atmosphere. 

You see, everything started with an angle!

Angles are nature’s most innate phenomenon. They set the rhythm, discipline, and a pattern in nature. Why does each petal in a flower inclined in such a way that it looks beautiful? Why is it that every branch of the tree gets that perfect angle to reach the sunlight? Do you think the mighty rivers would flow straight and meet the never-ending ocean? There is a pattern, an unbiased way in which nature thrives. And for me this pattern is none other than "angle". 

The word "angle" comes from the Latin word, angulus meaning corner, cognate words according to New World Encyclopedia Greek ἀγκύλος (ankylοs), meaning “crooked, curved,” and the English word “ankle”. However, both are connected to the Proto-Indo-European (PIE) root ank-, meaning “to bend” or “bow”. Many scholars debated the angle definition, but today, we accept the Euclidian- right, acute, and obtuse angles! And these angles play a significant role above our planet to the dark secrets the caves behold. 

The thirst for exploring every nook and corner of this planet led humans to seek shelter in caves. Caves provided them protection from large animals and a safe place for slumber. I have always pondered about the factors affecting cave selection. Did the humans choose smaller caves or bigger caves? What must have been the criteria for selection? For what I believe is then, the angle/inclination of the cave entrance must have played a major role. For instance, the entrance with an angle of thirty degrees will always be safer than a barometric cave (the one with an opening parallel to the ground = 0 degrees). This is one very important aspect of early human life that we never looked at. 

The thirst for knowing the depths led humans to measure and explore these magnificent and unique subterranean ecosystems. The first known cave map dates back to man-made cave in tufa called the Stufe di Nerone (Nero's Oven) in Pozzuoli near Naples in Italy and the first natural cave to be mapped was the Baumannshöhle in Germany in 1656. However, it was only in the early 19th century, when cave explorers developed technical cave mapping methods (using instruments), it was realized that the length of the cave passages alone was insufficient for making a map. Instead, a combination of six essential measurements laid the foundation of any cave survey for mapping. These magical measurements are; Left (distance between the cross-section to the left wall), Right (distance between the cross-section to the right wall), Up (the distance between the cross-section to the cave ceiling), and Down (the distance between the cross-section to the ground), Inclination (the angle at which the cave is inclined at the survey station) and Azimuth (Direction of the cave every survey station). Traditionally, caves were measured manually using tape, rope, a clinometer (for measuring angle), and a compass at sequenced survey stations spaced up to ten meters apart. Then, the details were obtained by sketching the cave passages on a graph sheet. However, these methods were time-consuming and prone to human errors. Now, modern gadgets such as handheld laser distance meters have been increasingly employed instead of tape to acquire range measurements between survey stations, LRUD, and comprise of an inbuilt clinometer and compass. The details are then converted using various computer software. Also, there is a laser scanning method that is expensive yet, a fast way to get a highly accurate cave map. 

I too began primitive. I along with my team left our field camp on a mission to survey our first cave using traditional methods. Into the deep lush green evergreen forest, we thought, how do we map our first cave? All the way, we kept on planning about each one’s roles and tried deciding on the length of the survey stations. Not well equipped, we carried a rope, a long measuring tape, and a protractor! It was our first try with the traditional method, and we spent numerous hours mapping a 30-meter-long cave. We were hungry and tired; one of my colleagues asked me why can't wait for the highly accurate laser meter? Confused as to what to reply, I thought, in the 19th century, if the explorers had waited, was there a chance of evolution? 

Evolution in methods in cave surveying/mapping today gave us a boon to what we call a laser meter. A few months later, when we mapped the same cave with a laser distance meter, it just took us 60 minutes for the survey, and I remembered how we were swamped holding the tape and trying to figure out how to measure the angle! 

Finally, the never-ending journey of measuring the deep dark wonders began and after measuring numerous cave passages I have realized that on life’s journey or a cave survey, the angle is all that matters. 

I, along with my field assistant surveying a limestone cave using a laser distance meter and manually noting the measurements