Original: In 1847 Wallace and Bates discussed the idea of an expedition to the Amazons , the plan being to defray expenses by sending specimens back to London where an agent would sell them for a commission , and for the travellers to '' gather facts towards solving the problem of the origin of species '' , as Wallace put it in a letter to Bates .
Simplified: Also , for the travellers to '' gather facts towards solving the problem of the origin of species '' , as Wallace put it in a letter to Bates .