that when the rake bar 7 is fixed in position the tines 81 of the rotating drum assembly 5 mesh with the tines 101 of the rake bar 7 the length of the tine 101 i e the distance from the centre 109 of the bar 93 and the tip 111 of the tine is 215 millimeters the distance between the main shaft 55 and the mounting bar 93 of the fixed rake bar is 368 millimeters which means that the resultant interlock between the two sets of tines 81 and 101 is 5 75 centimeters the rotating drum 5 is housed within the casing the base of which is defined by feed table 35 and the back of which is defined by a removable back cover 113 the sides of the drum chamber are defined by the sides of the cover 37 and the top of the chamber is defined by an internal ceiling 115 the internal ceiling 115 extends from the top of the front of the cover 37 and divides the space therein to define an upper area where the vacuum suction means 13 is housed the internal ceiling 115 is shaped and positioned so as to help to guide passage of the hay and straw through the apparatus the hay and straw is fed into the apparatus in direction x manually through the input 3 the hay and straw is pushed forwards until it is engaged by the tines 81 of the rotating drum 5 the rotating drum 5 engages the hay and straw and lifts it upwards in direction y where it then meshes with the rake tines 101 the hay and straw is then combed.