Cheesburgers are not possible before refrigeration and modern farming. The really soft burger buns were not very possible but around harvest time something approaching it was possible. Later breads got dryer. Cheese keeps itself but the mild cheese on cheeseburgers not that long unlike the cavey ones. In general it was not made until later in the year. Beef can be had at anytime but in general it was kept ofr fattening during the summer.