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IN the days when iron pipe was more expensive than It now IS, and wood cheaper, it was a common practice to bore logs lengthwise and to use them for carrying water underground, often for long distances. It was an easy matter to bore accurately in the center of logs hecause, in the kind of wood chlsen for the purpose, a small open or pithy “heart” extended through it. This was vel'y small, usually but Uttle larger than a pin, but it was sufficient; for the worm of a bit found it to be “the line of least resistance” and would follow it. While this sort of wooden pipe is rarely to be desired, nowadays, it is sometimes desirable to have a wooden tube and to Imow how to make H. By making it in two parts one may arra n ge to guide the bit in much the same manner as did the old time aqueduct makers, and even more accurately. These parts should be gotten out as shown in end view in the drawing, the two inserted tongues, a. (, serving to hold them relatively in place and to make the joint tight. Along what is intended for the center of the hole a deep gage mark is made, and, with a corner chisel or other tool,-a small triangular section is removed for the whole length so that when the two parts are clamped together a small square hole will extend through where the center of the final hole is to be. The size this “pilot” hole should be depends upon the size of the bit or auger to be used. For a large auger it will not need to be more thaI an eighth of an inch square, and for a small bit the gag8 mark alone will often be found sufficient. H must be large enough so that the point of the worm will enter it, but small enough so that the bit will be firmly guided and drawn forward. When boring the paris must be very firmly held together and the bit must be drawn out as often as the pod fills with shavings. For the latter reason it is advantageous to have a bit with as long a pod as Blank for a wooden tube and double crank for auger. is available. The shank af the bit is best lengthened by welding a steel rod to it. For turning it a common brace may be used; but if much work of this sort is to be done, it will be found to be accelerated by having the end of the rod bent into a double crank, like that commonly used on “ship augers,” as illustrated. This is operated by taking hold at A and B with each hand. It requires a Uttle practice to enable one to turn the cranks thus without making the bit wabble considerably; but as soon as one gets the knack he can do the work much faster than with a lrace, and much mQre easily
