8 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



of explosives seems to be an almost perfect plan ; but it remains 

 to be seen whether trees planted by this method do so very much 

 better than those on spade-dug ground, as has been asserted in the 

 United States of America. 



The question as to the time of year the explosive should be 

 used must remain unanswered until more experience has been 

 obtained. If we had the gift of accurate prophecy of the weather 

 during the winter and early spring months, I am inclined to think 

 that early in the winter would be the best time for comparatively 

 light soils and later for heavier ones, especially in a wet season. But, 

 generally speaking, probably February is the most favourable time, 

 so that if wet weather should tend to clog the seed-beds they may 

 be well drained at any rate during the first season. 



The mode of manipulation is a simpler matter to deal with, at 

 any rate as regards the actual application of the charges ; but their 

 size and their distribution probably require further experience before 

 the most efficient mode of use can be said to have been determined. 



Besides cartridges, detonators, and fuse, the apparatus required 

 consists of a pointed bar (about ij inch diameter and about 4J feet 

 long), with which to make the holes ; a heavy hammer, with which to 

 drive the bar ; a straight wooden stick about an inch in diameter and 

 cut square at the end, with which to stem and tamp the holes ; a pair 

 of sharp secateurs, with which to cut the fuse with clean straight ends ; 

 and a small pair of gas pliers, with which to nip the detonators tight on 

 the fuse. Fuse and detonators are not required if cartridges fitted 

 with electric ignition are used, but their extra expense probably hardly 

 covers the advantage of simultaneous discharge of a number of shots. 



Each cartridge has to be prepared at the time of use with fuse 

 and detonator. First the end of the fuse is freshened with a clean 

 square cut, for fear that the end of the core may have been deteriorated 

 with exposure in storing ; next the detonator is carefully emptied 

 of the packing sawdust by a few jolts, and gently pushed home on 

 the end of the fuse ; with the gas pliers the edge of the copper is 

 slightly nipped, so as to hold the detonator firmly on the fuse. Of 

 course care will be taken not to pinch the charged end. Thus pre- 

 pared, the detonator is pushed into the substance of the cartridge, 

 in which it may be necessary to make a hole with a pointed piece 

 of stick (this is always the case if solid explosives, such as gelignite, 

 arc used ; these, through having nitroglycerin in them, are dangerous 

 to use in frosty weather). The paper case is now tied with twine to 

 secure it on the fuse. The charge is now ready to be placed in the 

 hole. The holes are made vertically downward, and should be quite 

 three feet deep. From what I have seen of shallower holes, I venture 

 to think that three feet is the minimum depth to be advised, and 

 that in reckoning the depth allowance should be made for the distance 

 to which cultivation has loosened the topsoil. Thus, if the soil is 

 fairly loose for a depth of a foot, it might be reckoned as only half 

 that amount, and the hole made to 3 feet 6 inches from the surface. 



