OIL AND GAS WELL EQUIPMENT-NAMELY, DRILLING RIGS, VACUUMACTUATED MUD MIXERS FOR MIXING MUD FOR ROTARY DRILLING, ROTARY PUMPS, ROTARY DRILLING AUXILIARY UNITS EACH COMPRISED OF PUMP, ENGINE, AND COMPLETE V-BELT DRIVE MOUNTED ON A STEEL BASE, STEEL PROTECTIVE SAFETY GUARDS FOR MOVING MACHINE PARTS, AND AIR-GAS STARTING UNITS FOR INTERNAL COMBUSTION ENGINES