19 on posts 21 and horizontal movement of carriage 20 on rods 22 so that the carriage is located over the opening 15 and lowered into the opening so that the gripper means shown schematically at 23 in fig1 is lowered down to the upper end of the parison 13 to be removed the position of the elements at this time is as shown in fig3 the piston within cylinder 24 is raised thus raising the rod 33 and the push piece 34 as well as the ring 35 at this point the operation will be described specifically with respect to its action on the closing jaw 43 it being understood that an identical action takes place with respect to the closing jaws 53 and 63 as the elements 33 and 34 move downwardly first of all the inner surface portion 47 of ring 35 moves beneath the portion 45 and engages the back 47a of the jaw 43 this causes a turning movement of the jaw 43 about the axis of pin 42 to the closed position as shown in fig4 downward movement of the ring 35 is limited as the bottom portion 48 of the ring engages the ledge 49 of the closing jaw 43 however even after this downward movement of the ring 35 has been limited the push piece 34 continues moving downwardly to enter the upper end of parison 13 as shown in fig4 a firm grip of the parison is then achieved as the tapered lower end of push piece 34 flares the parison outwardly and urges the material of the.