In each question, the first and the last sentences of the passage are numbered S1 and S6 respectively. The rest of the passage is split into four parts. These four sentences are jumbled. Read the sentences and identify their correct and logical order.

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S1: But Mr. Ford was by no means the inventor of mass production.
P: It is difficult, indeed, to say who was.
Q: Brilliant men perfected cotton gins and looms.
R: The invention of the steam-engine gave manufacturers the cheap power they needed.
S: When the first large mills for the manufacture of cloth were built, mass production began.
S6: When one huge machine began to perform rapidly due operations previously done slowly by hand, the age of mass production was born.
The Proper sequence should be: