Britain and France.  But the stored supplies were on hand in the South, locked in by the blockade and would be available when the war was over provided the war did not take on an uncivilized and sanguinary character through a rising of the slaves.  If that occurred cotton would be burned and destroyed and cotton supply to Europe would be not merely a matter of temporary interruption, but one of long-continued dearth with no certainty of early resumption.  Fearing the growth in England, especially, of an intention to intervene, Seward threatened a Northern appeal to the slaves, thinking of the threat not so much in terms of an uncivilized and horrible war as in terms of the material interests of Great Britain.  In brief, considering foreign attitude and action in its relation to Northern advantage—­to the winning of the war—­he would use emancipation as a threat of servile insurrection, but did not desire emancipation itself for fear it would cause that very intervention which it was his object to prevent.

His instructions are wholly in line with this policy.  In February, 1862, the Confiscation Bill had been introduced in Congress.  In April, Mercier’s trip to Richmond[897] had caused much speculation and started many rumours in London of plans of mediation[898].  On May 28, Seward wrote to Adams at great length and especially emphasized two points:  first that while diplomats abroad had hitherto been interdicted from discussing slavery as an issue in the war, they were now authorized to state that the war was, in part at least, intended for the suppression of slavery, and secondly, that the North if interfered with by foreign nations would be forced to have recourse to a servile war.  Such a war, Seward argued, would be “completely destructive of all European interests[899]....”  A copy of this instruction Adams gave to Russell on June 20.  Eight days later Adams told Cobden in reply to a query about mediation that it would result in a servile war[900].  Evidently Adams perfectly understood Seward’s policy.

On July 13, Lincoln told Seward and Welles of the planned emancipation proclamation and that this was his first mention of it to anyone.  Seward commented favourably but wished to consider the proposal in all its bearings before committing himself[901].  The day following he transmitted to agents abroad a copy of the Bill that day introduced into Congress embodying Lincoln’s plan for gradual and compensated emancipation.  This was prompt transmittal—­and was unusual.  Seward sent the Bill without material comment[902], but it is apparent that this method and measure of emancipation would much better fit in with his theory of the slavery question in relation to foreign powers, than would an outright proclamation of emancipation.