360 RECENT DEVELOPMENTS IN THE NICTAUX IRON FIELD. 



From this it is obvious that two veins were passed through, 

 both of which flatten with depth. (See Plate V.) 



Plate VI is a plan showing the surface features of the locality. 



A few notes collected by the writer relative to the rate and 

 cost of boring with this drill as proved by practical experience 

 may be found interesting : 



In boring the 620 feet hole on the Wheelock Farm 1560 

 hours were employed, which time included that taken up in the 

 drawing of rods, sharpening bits and cutters, and other minor 

 delays, so that fairly deducting say 25% of this, it would leave 

 620 feet of core produced in 1170 hours of actual drilling, or an 

 average rate of boring was attained of over 6 inches per hour. 



The cost of boring this hole may be very approximately set 

 down at $2.00 per foot, made np as follows : 



Labor $670.00 



Management 250 . 00 



Fuel ; 195.00 



Lighting, oil, waste, etc 35 .00 



Shot 50.00 



Wear and tear . ... 50.00 



$1250.00 

 In considering the above, it must be borne in mind that the 



o * 



rock here though composed of slates and shales, is very hard, 

 and often intercalated with quart/ite, and highly ferruginous 

 bands; and further, though the drill runner is a competent 

 man, all the conditions at first were new, and consequently both 

 the cost and rate of boring will probably be materially reduced 

 as the operations progress. 



In order to show that this hole was a severe test, the record 

 of no. 2 may be taken in comparison, and it will be seen that on 

 the average- over 1 foot per hour was bored, while from 4 feet 

 to 6 feet per hour was done. in the softer portions of the rock. 



The cost of boring in this softer rock is also reduced by the 

 fact that the cutter is used instead of shot, which latter method 

 is not only expensive in the consumption of shot but also of shot 

 barrel, which costs about $2.25 per foot, and wears away at the 

 rate of about 1 foot of barrel in 50 feet of rock. 



