Shock inducing well tool

Claim 1

A DOWNHOLE SHOCK-INDUCING TOOL ADAPTED TO BE POSITIONED IN A BODY OF LIQUID WITHIN A WELL AT A LEVEL OPPOSITE AN EARTH FORMATION TO BE TREATED WHICH IS IN CONTACT WITH SAID BODY OF LIQUID, SAID TOOL COMPRISING, A LONGITUDINAL HOUSING MEMBER OF A DIAMETER TO PASS DOWN THE WELL TO THE DESIRED LEVEL, SAID HOUSING MEMBER HAVING A CHAMBER FORMED THEREIN AND PORT MEANS THROUGH A WALL THEREOF TO THE CHAMBER; LOCATING MEANS SECURED TO SAID HOUSING MEMBER FOR POSITIONING SAID HOUSING MEMBER WITHIN THE WELL ABOVE THE BOTTOM THEREOF; CHAMBER-EVACUATING MEANS CARRIED BY SAID HOUSING MEMBER FOR CREATING A CONDITION OF REDUCED PRESSURE WITHIN A CLOSED PORTION OF THE CHAMBER; NORMALLY-CLOSED VALVE MEANS OPERATIVELY ASSOCIATED WITH SAID CHAMBER-EVACUATING MEANS AND SAID PORT MEANS TO CLOSE ALL OF SAID PORT MEANS WITH RESPECT TO SAID PORTION OF THE CHAMBER AT LEAST DURING THE EVACUATION THEREOF, SAID VALVE MEANS BEING ADAPTED TO OPEN SAID PORT MEANS TO SAID PORTION OF THE CHAMBER AFTER CREATION OF SAID CONDITION OF REDUCED PRESSURE THEREIN; AND, ACTIVATING MEANS CONNECTED TO SAID CHAMBER EVACUATING MEANS FOR SELECTIVELY OPERATING SAID CHAMBER-EVACUATING MEANS.