2623. Sanders, R. C. Feb. 2. Horticultural knives.-In a knife for making T-shaped incisions, the blade is projected against the object to be cut by a spring, and is withdrawn, and released to be projected again, by a trigger arrangement. The blade comprises an ordinary straight knife blade a, Fig. 1, and a spear-shaped blade b placed on the cutting-edge of the blade a. The blades are fixed in a block c, which slides in a tube d and is pressed forward by a spring. A tube k, situated below the tube d, holds a sliding piece l, which carries a spring having a projection n engaging a notch in the block c, and which is moved by a trigger m against the action of a spring. When the piece l is moved sufficiently to bring the spring into contact with the partition wall between the tubes d, k, the projection n is withdrawn from the block c, and the block and knife are forced forward by the spring in the tube d. The knife projects through a nozzle f, which is forked to embrace the branch to be operated upon and grooved to allow of the passage of the knife.
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