RECENTLY PATENTED IMPROVEMENTS. 665 



wells with such improved water-lifting devices as will render their construction 

 and repair more certain of accomplishment, and their operation comparatively 

 more reliable than heretofore. 



It has been found in practice that, owing to the nature of the ground through 

 which the greater number of tube wells are bored, the cylinder corrodes so as to 

 be within a short time almost or entirely unfit for service. 



In order to remedy this defect it is proposed to galvanize the cyHnder both 

 internally and upon its outer surface. 



Heretofore much difficulty was had in driving check-valves to their seat at 

 the lower extremity of the cylinder or driving-barrel. As there was practically 

 nothing connected to them that would keep them in a vertical line with the cylin- 

 der, they would, as it were, attempt to turn end for end, and in many cases would 

 come to and be left upon their bearing in an oblique position. 



A check-valve under such circumstances could not fully accomplish the object 

 which its name implies. An improved check-tube is closely encircled near its 

 lower end by a turned ring which has a diameter corresponding to the bore of 

 cylinder. 



When the check-tube is being driven to place the drill-rod is attached to its 

 upper end and a rubber packing-ring having a plain outer surface, guides the 

 upper end, and the turned ring holds the lower end in a central position. 



The said packing-ring has a flaring internal surface, and it is expanded by a 

 correspondingly tapered cone upon the check-tube. Each of these parts is con- 

 structed with smooth surfaces for reasons explained further on. 



The check-tube can only be driven downwardly until the coned surface 

 comes in contact with a beveled seat flared from the internal diameter of the 

 turned ring at its upper edge. 



Heretofore, owing to the absence of such a seat to limit its movement, the 

 check-tube has been driven so far within the packing-ring that the latter would 

 interfere with the perfect working of the valve, and the packing-ring (usually rec- 

 tangular in cross-section) would be compressed until when required its removal 

 would be very difficult if not impossible. 



The smooth surfaces of the improved cone and the comparatively small 

 body of rubber forming the packing-ring render the withdrawal of the check-tube 

 quite an easy matter. When the check-tube has been fully driven to place, the 

 lower edge of the packing-ring is in contact with the upper edge of the turned 

 ring. 



An internally threaded thimble is attached to the lower extremity of the 

 check- tube and prevents the same from being drawn upwardly without carrying, 

 with it the turned ring. This latter is secured internally at its lower end forming 

 a concentric shoulder which is engaged' by the upper edge of the thimble. 



The lower edge of the turned ring or follower rests upon the top edge of the 

 sand-point coupling. This coupling has an external diameter corresponding to 

 the cylinder.bore and its lower edge rests upon a concentric shoulder projecting 



