BORED AND PUNCHED WELLS 



93 



to the considerable weight of the earth lifted, a windlass or some 

 form of tackle is sometimes required to lift it to the surface. It 

 may be necessary to pour water into the hole to give sufficient 

 coherence to the materials to cause them to cling to the auger. 



For medium-sized wells, larger forms of the same 

 general type are frequently used, augers of the stand- 

 ard shape with diameters of 6 or 8 inches being not 

 uncommon. In general, however, special forms, sim- 

 ilar to those described in the following paragraph, are 

 used. 



For boring wells of large size, from 6 to 36 inches 

 in diameter, some one of the various patented forms 



are generally used. The com- 

 mon shapes are illustrated by 

 Figures 37, 38 and 39. The 

 method of work is shown by 

 Figure 40, while a special form 

 of bit for lifting boulders is 

 illustrated by Figure 41. Nu- 

 merous other forms are in use 

 locally. 



The 2- and 3-inch wells 

 are usually equipped with i- 

 or 2-inch-iron pipes, leading from the sur- 

 face to a point a few feet below water 

 level. Where the material in which a 

 well ends is coarse enough so that it will 

 not clog the pipe, a number of small holes 

 are drilled near the lower end to facilitate 

 the entrance of the water. On pumping, 

 the finer material is raised with the water 



through the pipe until the remaining coarser particles form a 

 natural filter around the pipe. Pebbles are sometimes inserted 

 through the pipe to aid nature in forming such a strainer. (Fig. 

 42). In finer materials, a screen is often necessary (Fig. 36,4), 



FIG. 37. 



Common form 

 of well auger. 



FIG. 38. Common form of 

 well borer. 



