A system and method allows an email user to solicit an email thread from another user in situations where the first requesting user may have been added to an email thread after the email thread was started, or in situations where the user may have an incomplete thread. Units for calculation of the image features calculate image features of links A and B, respectively. Transverse sealers are provided between the seal element and at least the second part of the parts which are interconnected but torsionally free. This distance can be modified by means of an adjusting element by operation of a turning handle. The sledge also has an agitator including two posts and a bracket that extends between the posts for agitating the powdered material within the housing.