“you ought not to think an hour upon the matter, but to spring to action at once.”
what is the purpose of the words “hour” and “spring”?

In this particular line from The American Crisis, Thomas Paine, the intention of this particular line is used to insinuate a sense of urgency. This is done through the use of the word 'hour', to show that time is precious as even a short unit of time such as an hour now has great value. It is also done through the use of the word 'spring' to help the reader visually imagine a fast move to action.

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