From the foregoing, it will be apparent that the present invention brings to the art a new and improved drill 10 with body 13 with length L which is {HEAD ~ at least four times the diameter D} of {TAIL ~ tip end portion} 14 
From the foregoing , it will be apparent that the present invention brings to the art a new and improved drill 10 with body 13 with length L which is { HEAD ~ at least four times the diameter D } of { TAIL ~ tip end portion } 14
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH