314 



The " Buckeye " Ditcher. 



[July, 



August 24th to 27th, inclusive, gave the information concerning 

 the rate of digging 2 ft. 6 in. minors in wet clay. The column 

 headed ' ' Tons of earth excavated per hour ' ' was derived from 

 determinations of the density of the undisturbed soil and the 

 dimensions of the trenches. 



Table ITT. 



Type of earth 

 excavated. 



Depth of 

 trench. 



Chains 

 trench 

 dug 

 gallon. 



Chains 

 trench 

 dug per 

 hour. 



Gallons 

 per hour. 



Tons of earth 

 excavaied per 

 hour. 



Moist stilf clay. . 



3 ft. 6 in. 



•64 ch. 



17 ch. 



2-8 gal. 



18 tons 



Moist stitt' clay. . 



2„ 6 „ 



176 „ 



3-0 „ 



2-0 „ 



25 „ 



Dry clay with 













flints and chalk 



3,, 6 „ 



1-30 



3-0 „ 



2-3 „ 



31 



Dry clay with 













flints and chalk 



2 9 



1-78 „ 



4-6 



2-6 „ 



37 



Dry clay with 













flints and chalk 



2 ,, 



3-41 



9-0 



2-6 „ 



52 



• It will be observed that the rate of excavation measured in 

 chains per hour increases rapidly as the trench becomes 

 shallower, the type of soil being the same. This is due not 

 to the machine excavating a lesser weight of earth per hour, 

 for the last column in Table TTT shows that the weight of 

 earth excavated increases rapidly as the depth of trench 

 decreases; nor is it due to a higher lift, which in each case 

 is the same. The increase in speed with the shallow drains 

 is due in part to lesser friction between the digging wheel and 

 the sides of the trench. Indeed, this friction accounts for a 

 great proportion of the power used in digging, and is well 

 brought out in comparing the rate of digging 3 ft. 6 in. 

 trenches in moist clay at 1.7 chains per hour with 3 chains 

 per hour for trenches of the same depth in dry clay, in which 

 the friction is much less. 



The rate of fuel consumption, given in gallons per hour in 

 the fifth column of the table, is roughly constant at all speeds. 

 It varies in fact from 2 to 2.8 gallons per hour. One of 

 the reasons for this constant consumption of fuel is that the 

 machine is fitted with an automatic cut-out, which acts like 

 a governor and causes the engine to run at constant speed. 



The table also gives an indication of how much work could - 

 be done under the various conditions of depth and soil if it 

 were kept running, e.g., for 7 hours per day. Under these 

 conditions some 63 chains of 2 ft. minors could be dug in 



