When the drilling-tools have been 'strung tip,' the crown-block is moved if necessary to allow the bit to strike 15ottom in the same vertical line as the slot in the walking-beam for the reason that the latter supports the tools later on. As the stem and bit are over 30 ft. long and extend above the beam, it will be seen that other means must be provided to deepen the well to a point where the temper screw can be used. This method is called 'spud ding-in' and is carried out as follows : The bull-rope is placed on the bull-wheel, the tools lowered to the cellar-bottom and enough slack run out from the bull-wheel ' to permit connection to the crank-shaft by a manila jerk-line. A spudding-shoe (Fig. 89), which is anchored by a bridle fastened .to the back derrick-sill, is placed over the drilling-cable and a clevis passed through an eye in the jerk-line to the lugs of the spudding-shoe. The spudding ring is put on over the wrist pin, which has been previously placed in the second hole of the crank-shaft and the outside eye of the jerk-line over the spudding ring. All slack in the cable is then taken up by the engine until the tools are lifted from the bottom, when the bull-rope is thrown off and the engine allowed to run, raising and lowering the tools by the off-set in the crank-shaft. As the bit digs away, it can be kept striking at bottom by raising the bull-wheel brake and slacking the cable from time to time. Enough water should be used to thor oughly mix with the cavings, but too much water should be avoided as caving of the walls might result. Guides of wood are usually nailed around the stem at the floor to keep the stem dropping in a vertical line while the helper, or tool-dresser, turns it to avoid dig ging a flat hole. Turning the tools by hand usually continues until a depth of from 75 to 100 ft. has been attained,-when the spring in the line will turn them without further aid.
When the hOle becomes so muddy that the bit no longer drops freely, the bull-rope is put on, the spudding-shoe disconnected from the cable and the tools withdrawn above the hole and swung aside ; the bailer is pulled from its resting place and lowered to bottom, where it is 'spudded,' that is, raised and lowered to bottom several times to pick up as much mud as possible. The bailer is then raised and its contents discharged into the dump-box. The opera tion is repeated until the drillings have been removed,' when the tools are again run to bottom and spudding resumed. In drilling at any depth, it is always important to keep the hole as clean of drillings to allow a free drop to the tools. In ;this way, 5 to 8 feet is made at a time. Should the walls begin caving at the surface, it is usual to place a wooden conductor in a well to a suffi cient depth to exclude all cavings. When the stem is deep enough to be covered by the walls, the wrist-pin. is placed in the third hole of the crank-shaft to permit of a longer stroke and a harder blow, and when a depth of from 130 to 150 ft. has been attained it is cus tomary to substitute the walking-beam for the jerk-line. This is called 'hitching on'. The temper-screw is placed in the slot on the beam and a counterweight rigged back of the sampson-post to aid in pulling back the screw after it has been let out. The temper screw (Fig. 91) consists of a 2-in. by 5 or 6-ft. screw with coarse, square threads which run through a box having wings at the lower end, where a split clamp held together by a set screw, is placed. A tee rests upon the nose of the beam, and two guides or reins run the length of the screw to the box. Attached to latter in notches at the top edge are the 1-in. links, by which the wire or manila line is suspended. The manila clamps (Fig. 92)
are larger at the top than the bottom to permit of a wrapper of soft rope, usually about 5 ft. long, being applied to the cable on the line just above the clamps. When the bull-wheel brake is raised, the line pulls the wrapper tightly into the clamp, forming a tight wedge with the latter. The wire-line clamps (Fig. 93) are composed of two straight pieces of steel with grooves running through the centres to fit the size of the line being used. In each case a heavy iron 'C' having a set screw is used to tighten the clamps.
When lowering the tools into the well, the driller does not run them to bottom at once but applies the bull-wheel brake at inter vals of a few feet when nearing the bottom in order to get the full stretch of the cable. In other words, the tools strike bottom on the spring of the line when drilling and the rebound is probably several feet. This action materially aids in mixing the cuttings with the water. In ordinary drilling, due to the spring in the line, the beam is returning on the up-stroke when the tools are striking, creating a distinct jar on the rig, which grows more pronounCed in a hard formation, especially when the wire-line is in use. Drilling usually proceeds in the open hole until the walls begin caving or until a sufficient depth has been obtained to insert the casing. \Vhere stove-pipe is used, from 200 to 500 ft. is the ordinary depth, depending upon the method of lowering it. The stove-pipe used for casing in California is held together by dents made by picking, and care should be taken to avoid pulling the column apart. A depth of 200 ft. is ample when the string is being lowered without support, but some operators prefer putting it in on a_ smaller string of casing, in which case it rests upon a casing-spear or upon a cast iron bushing attached to the bottom of the screw-pipe. The bush ing has a left-hand thread and can be detached from the screw casing and left in the well where it is easily drilled up. Five hun dred feet or more of stove-pipe can be lowered in the well in this way without injury. For lifting and handling this class- of casing, wooden friction blocks 16 by 16 in. by 5 ft. are securely bolted around the pipe by four 1-in. bolts ; a wire-line sling is placed on the casing hook and under each side of the friction blocks, so that the column can he moved by the calf-wheel.' The stove-pipe in lengths of 10 or 20 ft. is coupled together by placing a drive-head on the top joint and dropping the tools on the column, by 'bull-roping: that is, raising and lowering the tools on the drive-head (Fig. 94) by the bull-wheel. Should the coupling be too tight for bull-roping, the jerk-line and spudding-shoe are used as in spudding-in, and the casing driven together. The latter method is also used in driv ing or forcing the whole column of pipe when it does not follow or sink by its own weight. By placing the wrist-pin in the fifth hole of the crank-shaft to lengthen the stroke or drop of the stem, an unusually hard blow can be delivered. Hydraulic jacks are sometimes used to force the column clown but are not as effective as driving with the stem. For this work, two 6 by 6 by 16-in. pieces of iron are securely bolted by by 14 in. bolts to the upper tool-wrench square shank of the stem. These are called drive-clamps (Fig. 95), and strike upon the drive-head, which sets inside of the casing upon the main column, at the same time projecting over and resting upon the top coupling or section. These heads, which are bored to admit passing over the stem, are used for all sizes of screw casing to protect the threads of the top coupling as well as for driving to loosen the casing should the latter become fast from cavings.