A mortar includes at least one barrel mounted movably over a ball journal in a bottom supporting device, and an aiming device serving to aim the barrel vertically and horizontally. In order to be able to aim the barrel of the mortar automatically in a simple and cost advantageous manner, the aiming device preferably comprises a carriage that can be moved along guideways essentially horizontally towards or away from the barrel. At the carriage, the first end region of a pivoted arm is mounted so that it can be rotated about a pivot axis, and the second end region of the pivoted arm is connected with a spherical plain bearing, guiding the barrel. The spherical plain bearing embraces a housing part, which is open at its end faces and in which an inner part is mounted spherically (rotatably), which contains a cylindrical barrel guide, for movably accommodating the barrel.