258 The Trials of Hand-Power Powder Sprayers. 
Messrs. Hartjen sent the “Holder” Knapsack Powder 
Sprayer. This is another useful machine and ran very 
close for second place. The “ Holder ” is light and easily 
taken to pieces for repairs or renewal. The price of this pump 
is 32s. 6d. and the capacity 26 lb. The bellows are of single 
stroke action. 
All the knapsack powder pumps are worked by one man. 
Messrs. Gratton and Son, Boston, Lines., showed a pump on 
wheels worked by two men, a chain feeding the powder to 
blower. The difficulty with this style of feed is to get the 
small chain used to carry an even quantity of powder to the 
blower ; the latter is very good and the gear driving wheel 
easily turned. The price of the pump shown was 61. 10s. 
Messrs. Weeks, Maidstone, sent a very well made machine. 
It is carefully thought out and strongly built. The price of 
the hand-power machine is 61. 6s. Of the large machines 
this is the best. The great difficulty with all these machines 
is to get a regular feed to the blower the agitator used is 
of a small type and proved quite inefficient. If perfected in 
this direction it would make a very useful machine. Two men 
are required to work it ; the capacity is 22 lb. powder. 
Messrs. F. Randell, Ltd., North Walsham, sent a distributor 
worked by a plunger pump ; it is not very portable, and 
is open for improvement. The capacity is 20 lb., and the 
price 61. It is supposed to be worked by one man, but would 
require two. It is well and strongly made ; the blower very 
good indeed. This pump, again, is weak in its feed. 
The conclusion arrived at by the Judges was that for the 
particular purpose shown, viz., “ for applying dry insecticides 
in powder form to bushes or trees ” the portability and even- 
ness of distribution and ease of dismantling of the knapsack 
type were great points in their favour. It was felt that the fan 
system of blowing, as against the bellows, was perhaps the 
correct system, but until the powder can be fed more evenly to 
the blowing chamber the “ Knapsack ” scores. The difficulty 
with the chain feed is that it does not sufficiently agitate the 
powder, which banks up in the form of a tunnel over the 
chain and the feed ceases. A very similar action takes place 
with a finger agitator. These defects remedied, and a light, 
easily portable machine at a fairly low cost evolved, steps 
would be made in the right direction. 
Jas. M. Young. 
Charles S. Martin. 
