Engineering Wonders of the World
Volume III

340 ENGINEERING WONDERS OF THE WORLD. hauling upwards with the steam winch. In some cases the core is so stubborn that hy- draulic jacks have to be requisitioned to break it away from the mother rock. A core 15 inches or so in diameter, 8 to 10 feet long, materials, but so severe are the shocks to which it is subjected that it is small wonder that breakages sometimes occur. It is, how- ever, a comparatively simple matter to rescue a broken rod from a depth of some hundreds ARTESIAN BORED TUBE WELL AT BOURNE, LINCOLNSHIRE. INTERNAL DIAMETER, 13 INCHES ; DEPTH, 134 FEET. The water is seen issuing from the well at the rate of 3,480 gallons a minute, or 5,011,200 gallons per day. This is one of the most productive wells ever bored. {Photo, by courtesy of Messrs. G. Ider and Co.) and weighing a ton and upwards, neces- sarily offers considerable resistance by reason of its great weight, apart from this adhesive force. A string of rods and tools some hundreds of feet in length may be made of the very best of feet. The other rods are let down with a “ crow’s foot ” attached to the end. A “crow’s foot” Rl,^rieLin? Broken Tools. is a tool which will pass down a bore hole of a given size when this is occu- pied by a rod. It is first tried in a pipe of