...Marshal-Gen'l Dep. Missouri. There was a rich scene in the Yankee Congress on the 12th instant: Mr. Wilkeson took the floor and spoke at some length, principally in denunciation of Mr. Saulsbury 's speech of Friday last, charging him with uttering falsehood, and asserting that the President had been indifferent to the country, and sought at first to make the Confederates strike the first blow...