Collapsible derrick for drilling

Claim 1

IN A COLLAPSIBLE DERRICK FOR DRILLING OPERATIONS AND THE LIKE, A PAIR OF IDENTICAL COLUMNS SYMMETRICALLY SITUATED WITH RESPECT TO A VERTICAL PLANE OF SYMMETRY SITUATED MIDWAY BETWEEN THE COLUMNS, SAID COLUMNS EACH HAVING UPPER AND LOWER ENDS AND INCLUDING UPPER AND LOWER COLUMN ELEMENTS PIVOTALLY CONNECTED TO EACH OTHER SUBSTANTIALLY MIDWAY BETWEEN THE UPPER AND LOWER ENDS OF EACH COLUMN SO THAT THE COLUMNS CAN BE COLLAPSED AND RAISED BY TURNING MOVEMENT OF THE COLUMN ELEMENTS WITH RESPECT TO EACH OTHER AT THE CONNECTION THEREBETWEEN, A TABLE HAVING AN ELONGATED PORTION EXTENDING BETWEEN AND CONNECTED TO THE UPPER ENDS OF THE COLUMNS FOR SPACING SAID UPPER ENDS OF SAID COLUMNS FROM EACH OTHER, RAISING AND LOWERING MEANS OPERATIVELY CONNECTED TO THE COLUMNS FOR RAISING AND COLLAPSING THE SAME, AND EQUALIZING MEANS EXTENDING ALONG SAID TABLE IN THE SPACE BETWEEN AND CONNECTED TO THE UPPER ENDS OF THE COLUMNS FOR MAINTAINING THE TABLE WHICH EXTENDS THEREBETWEEN HORIZONTAL DURING RAISING AND COLLAPSING OF THE COLUMNS, SAID EQUALIZING MEANS INCLUDING AN EVEN NUMBER OF GEARS WHICH EXTEND BETWEEN AND ARE OPERATIVELY CONNECTED WITH THE UPPER ENDS OF THE COLUMNS AND WHICH ARE PERMANENTLY IN MESH WITH EACH OTHER, SAID GEARS INCLUDING A PAIR OF END GEARS, RESPECTIVELY SITUATED AT SAID UPPER ENDS OF SAID COLUMNS AND A PLURALITY OF ADDITIONAL GEARS SITUATED BETWEEN SAID END GEARS.