In accordance with this difference in the productions of the different regions of the earth, there seems to be a difference in the constitutions of the races of men formed to inhabit them. The tribes that inhabit Greenland and Kamtschatka can not preserve their accustomed health and vigor on any other than animal food. If put upon a diet of vegetables they soon begin to pine away. The reverse is true of the vegetable-eaters of the tropics. They preserve...