X ILLUSTRATIONS 



FIG. PAGE. 



37. Common form of well auger 93 



38. Common form of well borer 93 



39. Form of well lx>rcr 94 



40. Method of using well auger 94 



41. Special well auger for lifting boulders, etc 94 



42. Diagram showing advantages of packing with gravel 94 



43. Types of screens and well points 99 



44. Diagram showing formation of sand filter through pumping 100 



45. Diagram showing method of sinking jet wells by hand 103 



46. Diagram showing outfit and process of sinking the deeper jet wells 103 



47. Hollow bit used in jet process 104 



48. Paddy or expansion bit used for reaming 104 



49. Diagram showing danger of pollution when casing is carried only to rock. ... in 



50. Well strainers 114 



51. Diagram of suction pump and chamber 122 



52. Properly protected dug well with pitcher pump 123 



53. Properly protected drilled well with deep well pump 123 



54. Common arrangements of deep well pumps 125 



55. Common form of force pump 126 



56. Common form of force pump 126 



57. Siphon force pump 127 



58. Diagram showing principal of air lift 128 



59. Windmill supplying water pocket 131 



60. Artesian or flowing well 131 



61. Supposed conditions producing discoloration of waters in non-flowing wells. 139 



62. Conditions governing freezing in cased well 140 



63. Conditions governing freezing in wells with leaky casings 141 



64. Conditions governing freezing in limestone wells 142 



65. Combination well and cistern 149 



