The mother country represents Britain giving Manufactured goods to the British colonies back in America for a high price in return the Colonies in America are giving Gold, Silver, Fur, Lumber, and Food for a low price to Britain.
What you can say about this is the trade between Britain and American Colonies, the Colonies giving things for low prices and Britain giving the Colonies things but for high prices.
An example of the manufactured goods to the American colonies is that American colonies bought their cloth, furniture, knives, guns, and kitchen utensils from England.