Abstract: Sampling apparatus for installation on a predetermined path along which sets of printed and folded sheets are fed in overlapping relationship from the folder to the counter-stacker of a web-fed rotary press. The sampling apparatus comprises a divider mechanism which includes a divider blade and which is pivoted by a fluid actuated cylinder to and away from a working position, in which position the divider blade is disposed in the printed sheet path to cause several consecutive ones of the printed sheet sets to travel on one of its sides, where the path is open to a sample exit, and the succeeding printed sheet sets to travel on its other side. Immediately following the movement of the divider mechanism to the working position, an extractor mechanism comprising a pair of extractor blades is pivoted by another cylinder past the printed sheet path for delivering out of the sample exit at least the last of the several consecutive printed sheet sets travelling on the said one side of the divider blade.