... P. M., or about that time, had been busy at this work since three o'clock. The line of bluffs masked all view of the river; but, in fact, General Buell's Army of the Ohio was also now arriving from Savannah , on the opposite bank, below Pittsburg Landing, and Ammen's brigade, of Nelson's advance division, had been thrown across and placed in support of Webster's battery, at five o'clock. Generals Buell a...