Genesis 30:41
whensoever the stronger cattle did conceive: As the means which Jacob used would not in general produce similar effects, nay, probably the experiment was never in any other instance tried with effect, it is more in harmony with Divine truth to suppose that he was directed by some Divine intimation; and rendered successful, if not by a direct miracle, yet at least by the Lord's giving a new and uncommon bias to the tendency of natural causes. Gen 30:41