Greatest Feats of Engineering Part 12: Borobudur
Author: Steve Gore
In recent weeks this series has largely touched on modern or historically recent feats of engineering such as the Trans-Siberian Railway or the Hangzhou Bay Bridge. This week will be looking once again at the more ancient feats of engineering, accomplishments which may seem trivial to us as seen through the lens of modern technology, but which presented a major challenge to the people who built them.
This week I have chosen to look at Borobudur; a Buddhist monument in Indonesia dated to the late 8th century. Built along vaguely pyramidal lines, archaeologists have debated the intended purpose of Borobudur for years with two prevailing theories being that it is either a shrine dedicated to Buddha or a Buddhist temple. The temple monument is composed of 6 square platforms built one upon the other followed by a further 3 circular platforms. The base is 118m to a side and a total of 55,000 cubic metres of stone are thought to have been used in it's construction. The entire structure is covered in relief carvings and statues, most of which where remarkably well preserved when the site was rediscovered in the early 19th century.
Borobudur is inarguably part of the worlds cultural heritage and of particular importance to the Buddhist and Indonesian communities. But what makes it a feat of engineering? There are three things I discovered whilst researching this article that i found to be particularly compelling.
Firstly, the structure was built entirely without mortar. Every single one of the 50,000 cubic meters of rock used in the construction were quarried and transported to site and then locked into place through the use of dovetails, indentations and knobs. This represents a huge amount of planning as each stone would have to be cut to fit into a particular slot in the pattern.
Secondly, despite the fact that the Indonesians at the time had no standard unit of measurement and that such measurements that did exist were subjective to the individual performing them (e.g. the distance from the tip of the middle finger to the tip of the thumb when both were at their full extension) a survey conducted in the 1970s indicated a strong recurring ratio of 4:6:9 throughout the structure, this in addition to the precision employed in aligning the stone blocks and the positioning of the foundations to take advantage of the natural incline of the land demonstrates great care and time were taken to achieve such precise construction.
Lastly, the structure was clearly designed to take tropical weather conditions into account. An extensive system of drains and water channels serve to funnel rainwater away from the structure via 400 carved spouts. This level of foresight and planning has doubtlessly contributed to Borobudur's 1200 year longevity and the excellent condition it remains in today.
So, is Borubudur your greatest feat of engineering? Vote now to have your say.
Next week: The Trans-Alaska Pipeline