I am sure you know that Freemasonry started as a guild in ancient times. The guild contained freemen that were skilled builders. These master builders, masons, were more than builders, they were the architects and engineers of their time. If you saw the TV Mini-Series, “The Pillars of the Earth”, you saw a dramatized example of these men.
These masons were responsible for multi-year building projects that required a lot a skilled men. Those apprentices needed to be trained in the secrets only the master builder knew, such as “Lintels and Key Stones”. The masons also taught apprentices the use of simple tools, Compass, Square and Ruler, along with the Morals and Ethics required to start and then finish these massive building projects of their day.