192 DESTRUCTIVE INSECTS OF VICTORIA: 



MACHINES, AS USED IN FRANCE, FOR liSTJECTING 

 BI-SULPHIDE OF CARBON, ETC., INTO THE SOIL 

 SURROUNDING DISEASED VINES. 



{See Figs. 17 and 18.) 



With the advent of the phylloxera in France there resulted the 

 invention of several syringe-shaped " injectors " or pals injecteurs, 

 ■which have since proved of great value to French vine-growers as the 

 best means of injecting bi-sulphide of carbon into the soil surrounding 

 phylloxera-infested vines. 



One of the earliest machines made was that of M. Gastine. This 

 " injector " is composed of two principal organs, viz., a piston by which 

 the course is regulated, and a valve to retain the liquid which is dis- 

 solved under the influence of hydraulic pressure. In this apparatus the 

 liquid not only runs out, but is injected in a way that, if the hole begins to 

 get clogged, it is at once cleared by the pressure of the liquid. All the 

 "injectors" since placed on the market invariably have the two principal 

 organs above mentioned. The following advantages are claimed for 

 the Gastine "injector": — The injection is effected with certainty. 

 The outlet can never be blocked. The liquid is always passed through 

 in exactly equal doses. 



The working of this machine is extremely simple. The " injector " 

 is forced into the soil by the two handles and the pedal, and the 

 actual injection of the liquid is obtained by a single movement. It is 

 sufficient to push with the palm of the hand, the flat button-like handle 

 which forms the top end of the piston above the receiver. The piston 

 rapidly drops in the proportioning chamber in passing through the 

 leather ring. To leave at once where it has passed through the leather, 

 it condenses the liquid which fills the chamber of the tube just opposite 

 the plug of the " injector." Under the effect of the pressure which it 

 receives, it loses some of the properties that, supposing the liquids to 

 be incompressible, this last lets pass a quantity of liquid exactly equal 

 to that which represents the volume engendered by the descent of the 

 piston. The liquid so forced under the plug escapes with force through 

 the small outlet placed in the thickest part of the cone. 



The piston having gone as far as possible, the injection of the liquid, 

 ceases. The valve closes itself tightly and automatically under the 

 effect of a spring which is placed against the seat of the valve. The 

 piston, left to itself, mounts again to its old position. The liquid 

 precipitates itself into the empty space which it has left behind, and 

 the apparatus finds itself ready for a new injection. The different 

 motions above described are instantaneous. The springs employed for 

 working the piston and the retaining valve render the priming certain, 

 and completely automatic. 



Fig. 17 shows the Gastine machine, and Fig. 18 a section of the 

 same. 



