34 so that a positioned contact pin abuts against that surface the plug has a pivotable member 148a acted against by spring 150a and a slot 152a located to match a projection 154 on the guide block the socket pin 144b has similar numbered parts followed by the letter b and the plug mates with projection 156 on the guide block fig1 shows a schematic of the air control for the invention compressed air from a source not shown passes through line 158 control valve 160 line 162 and lines 28 and 30 and nozzle 164 and 166 for blowing contacts not properly aligned back into the bowls air also is directed through line 168 into pressure regulator 170 thence into an end of cylinder 52 the sequencing is controlled by five valves 172 174 176 178 and 180 as air enters through line 182 it passes through valve 172 and 174 and then through line 184 where it actuates valves 176 and 180 when the foot pedal 186 for valve 172 is depressed it exhausts air from line 184 through valve 172 and at the same time it introduces air through line 188 to activate valve 178 to introduce air from line 190 through line 192 to actuate gate cylinders 130 and 142 and lift cylinder 52 the air pressure from the pressure regulator 170 is lower than the pressure in line 192 so the gate cylinders.