f* The Hebei Invasion.The llev, Dr. Jacobs, Professor of Mathematics in Pennsylvania College, has just published a very interesting account of the Baltics at Gettysburg, with a faithfully delineated Map of the Battle-field, prepared' by himself hum actual measurements, and giving distinctly all the positions ol the contending armies. IIis notes on the Invasion are of* deep interest, aud will, we have no doubt, gne bi work a largo sale.We understand the ptice is but 60 cents acopy—certainly very low for the work, jTiimui'bu*bercthbethdafoui