From Albert G. Mackey and his Encyclopedia of Freemasonry, this installment of Symbols & Symbolism presents his exploration of the Broken Column. Note, some links have been added as reference to the original quoted sources.
The Broken Column
Among the Hebrews, columns, or pillars, were used metaphorically to signify princes or nobles, as if they were the pillars of a state . Thus, in Psalm 11:3, the passage, reading in our translation: If the foundations be destroyed, what can the righteous do? is, in the original, when the columns are overthrown, I.E..: when the firm supporters of what is right and good have perished.
So the passage in Isaiah 19:10 should read: her (Egypt’s) columns are broken down*, that is, the nobles of her state.
In Freemasonry, the broken column is, as Master Masons well know, the emblem of the fall of one of the chief supporters of the Craft. The use of the column or pillar as a monument erected over a tomb was a very ancient custom, and was a very significant symbol of the character and spirit of the person interred. It is accredited to Jeremy L. Cross (from the Masonic Chart) that he first introduced the Broken Column into the ritual, but this may not be true.
* This passage in Isaiah 19:10 reads: And they shall be broken in the purposes thereof, all that make sluices and ponds for fish. (KJV)