North American commercial activities including: major agricultural crops (barley, corn, wheat, coffee, tobacco, et cetera) and secondary agricultural crops (oranges, lumber, wine); primary mining extraction (coal, gold, silver, petroleum, et cetera); fishing grounds (including sponges); steamship routes (including nautical mileage between ports); navigable portions of rivers; and railroad lines broken out by time zone operations. Figures on the meridians give the time of day when it is noon at Greenwich.