“The common schools are the stomachs of the country in which all people that come to us are assimilated within a generation. When a lion eats an ox, the lion does not become an ox but the ox becomes a lion. So the immigrants of all races and nations become Americans, and it is a disgrace to our institutions and a shame to our policy to abuse them or drive them away.”

The Red Man, Volume X, No. 6 (July-August 1890)
The origin remains unclear. Gen. R. H. Pratt, "The Fathers of the Republic on Indian Transformation and Redemption" https://books.google.com/books?id=WMARAAAAYAAJ&pg=PA129&lpg=PA129&dq=%22schools+are+the+stomachs+of+the+country%22&source=bl&ots=Jcl8GbwmVC&sig=R-frEgg-6ZUZrx_UqCh1cqH4yb8&hl=en&sa=X&ved=0ahUKEwjPkOyV7a_PAhVC5iYKHajpD1sQ6AEINTAE#v=onepage&q=%22schools%20are%20the%20stomachs%20of%20the%20country%22&f=false, The Quarterly Journal of the Society of American Indians, Vol. 2, No.2 (April–June 1914), p. 129 cites "the columns of a little newspaper printed at one of the Indian schools during and prior to 1885". The Educational Weekly https://books.google.com/books?id=nWY0AQAAMAAJ&pg=PA519&lpg=PA519&dq=%22schools+are+the+stomachs+of+the+country%22&source=bl&ots=hTHXz7Q2AZ&sig=K_egMYGg8RNaVLKxEPiYt3w25mM&hl=en&sa=X&ved=0ahUKEwjPkOyV7a_PAhVC5iYKHajpD1sQ6AEISzAJ#v=onepage&q=%22schools%20are%20the%20stomachs%20of%20the%20country%22&f=false, Vol. 11, No. 222 (1 December 1881), p. 187 cites "a lecture referring to the maltreatment of the Chinese".
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