America’s First Sex Manual, 1766

Very interesting.

And thus those nobler parts we see
For such the parts of generation be:
And they who carefully survey will find
Each part is fitted for the use design’d:
The purest blood we find if well we heed
Is in the testicles turn’d into seed:
Which by most proper channels is transmitted
Into the place by nature for it fitted:
With highest sense of pleasure to excite
In amorous combatants the more delight.
For in this work nature doth design
Profit and pleasure in one act to join.

Indeed.