“So many enemies as slaves!”[165] Unless this ancient proverb has ceased to be true, there are now four millions of enemies intermingled with the Rebels, toiling in their fields, digging in their camps, and sitting at their firesides, constituting four millions of allies to the National Government. Careful calculation demonstrates, that, out of this number, more than one million are of an age for military service,--that in Virginia alone there are 121,564 male slaves of this important period, in Missouri 21,334, and in Kentucky 51,900. Can we afford to reject this natural alliance, quickened by a common interest, and consecrated by humanity? I call the alliance natural. Let history testify; and here I quote acknowledged authority. In the famous Peloponnesian War, when Greece suffered as we are suffering now, and her own people were arrayed under hostile banners, Greek meeting Greek, slaves often passed over from one side to the other, carrying sometimes oxen and sheep, and always practical knowledge of the country,--on one occasion twenty thousand in number, mostly mechanics: all of which is described by the great historian Thucydides,[166] who records also that the martial Lacedæmonians, in dread of their Helots, most cruelly took the lives of two thousand, selected for energy and character.[167] Thus in other days have slaves played their part, while slave-masters dwelt in fear. Of this trepidation there are abundant illustrations, some farcical. From Aristophanes we learn, that, during the same Peloponnesian War, the Athenians were unwilling to punish their slaves, lest they should desert. This dramatist, in one of his most famous comedies, has a character who, after exclaiming that “the slaves snore as never before,” pours forth his maledictions on the War, because he can no longer apply to them the wonted castigation.[168] The great philosopher of Greece accords with the historian and dramatist. Plato does not hesitate to say that “slaves and masters can never become friends”;[169] and he tells us how frequent are servile insurrections, especially in cities where the slaves speak one language, instancing customary outbreaks of the Messenians, and crowning his statement with the declaration, prompted by the universal human heart, even without experience as a slave, which had been his own lot, that “a man is a difficult possession to hold”:[170] and here our Fugitive Slave Bill with its terrible conditions, and the fugitive slaves of our country with their tragedies, are in harmony with this voice from Antiquity.