Isocolon

Isocolon is a rhetorical scheme in which parallel elements possess the same number of words or syllables. As in any form of parallelism, the pairs or series must enumerate like things to achieve symmetry. The scheme is called bicolon, tricolon, or tetracolon depending on whether they are two, three, or four parallel elements.
A well-known example of tricolon is Julius Caesar's "Veni, vidi, vici" ("I came, I saw, I conquered").
Etymology.
The term, a compound of "ísos" 'equal' and "kôlon" 'member, clause' was used in the classical Greek rhetorical literature:
The Greek plural is 'isocola', but 'isocolons' is also used in English.
Bicolon.
An example of bicolon is the advertising slogan "buy one, get one free" (you pay for one item but you get another free).
In Biblical poetry it is standard to see a pair of adjacent lines of poetry in which the second echoes the meaning of the first. This can be considered a bicolon. For example:
Tricolon.
A tricolon that comprises parts in increasing size, magnitude or intensity is called a "tricolon crescens", or an ascending tricolon. Tricolon can sometimes be a hendiatris.
Similarly, tricolon that comprises parts that decrease in size, magnitude, intensity, or word length is called a "tricolon diminuens", or a descending tricolon.
Abraham Lincoln used tricola in many of his speeches. His Gettysburg Address has the following phrase: "We cannot dedicate – we cannot consecrate – we cannot hallow..." Lincoln wrote in his second inaugural address, "with malice toward none, with charity toward all, with firmness in the right...", which became the most famous expression in the speech. Winston Churchill also used the device frequently, perhaps most famously in August 1940 when referring to the Battle of Britain with the line "Never in the field of human conflict was so much owed by so many to so few." In this instance, a frequent literary device of making the third colon stand apart in meaning from the other two for emphasis is employed (much/many/few).
Repeating the same thing multiple times is a special case of an isocolon, as a way of saying that only one thing is important, and it is very important. In about 1500, when Louis XII asked Giangiacopo Trivulzio what was necessary to win the war against Ludovico Sforza, Trivulzio answered: "Three things, Sire, Money, money, money!" In the 20th century, the cliché "Location, location, location" was said to enumerate the three most important attributes of real property. This phrase appears in print in Chicago as early as 1926, but is nonetheless frequently credited, incorrectly, to the British real estate magnate Lord Harold Samuel. British Prime Minister Tony Blair set out his priorities for office in 1997 with "Education, education, education".
Tetracolon.
Tetracola are sometimes called "quatrains" ("cf." the usual meaning of quatrain).
Example of Tetracolon may be cited from a poem of is Gabriele D'Annunzio:
Translation: It was raw mortar, and then it was terra cotta, and then it looked like bronze, and now it is a living thing
Another example can be cited from "Richard II", by Shakespeare 
Special cases.
A special type of collocation known as an irreversible binomial is a bicolon that is both short and so well known that it becomes a fixed expression. Not all irreversible binomials are bicolons or tricolons, however. Irreversible binomials generally consist of only a few words at most.
Examples of irreversible binomials that are bicolons or tricolons:
Examples of irreversible binomials that are "not" bicolons or tricolons: