692 ADDITIONAL EXERCISES 



Spraying Apparatus.- — Various forms of spraying apparatus are upon the market 

 for use in the different operations of spraying. The student is directed to trade 

 catalogs and to special treatises on the subject for details. 



We may, as an introduction to this subject, classify the types of spraying outfits 

 into: Bucket pumps (Fig. 238), knapsack sprayers (Fig. 238), barrel pumps (Fig. 

 239), the tank outfit, geared sprayers, steam and gasoline outfits, etc. 



The question of details resolves itself into a consideration of hose, extension 

 rods, nozzles, force pumps, wagons, push carts and receptacles for the spray materials 

 (for outfit see page 672). For these details and a list of firms dealing in spraying 

 apparatus, consult a bulletin by C. A. McCue entitled Plant Protection, Bull. No. 97, 

 Del. Col. Agric, Exper. Sta., June 15, 191 2. 



APPENDIX III 



Antisepsis and Disinfection. — An antiseptic is a substance which acts to the ex- 

 clusion from wounds of living organisms that cause putrefaction, or decay. 



Liquor Antisepticus. — 155 grains of boric acid should be dissolved in 113-^ ounces 

 of water, and 7 grains of benzoic acid in 2 3'2 ounces of alcohol, and the two liquids 

 then mixed. After dissolving 7 grains of thymol in a mixture of 8 drops of oil of 

 peppermint 4 drops each of eucalyptol and oil of gaultheria and i drop of oil of thyme, 

 triturate with 155 grains of purified talc and add the solution of benzoic and boric 

 acids. Shake occasionally during forty-eight hours, filter and add to the clear fil- 

 trate first i^i ounces of alcohol, and then sufficient water to bring the volume up 

 to I pint. 



Formalin. — Has powerful antiseptic properties. It is sold in 40 per cent, 

 solution and can be distilled with water to the required strength. 



Corrosive Sublimate (Bichlorid of mercury). — It is used in solution in water in 

 a strength of i : 1000. 



Definition of Disinfectant. — A disinfectant is a substance used to destroy the 

 germs of infectious diseases. The common disinfectants are formaldehyd (liquid, 

 gaseous), carbolic and (phenol) cresol, chlorinated lime (chlorid of lime), corrosive 

 sublimate. See Dorset, M.: Some Common Disinfectants. U. S. Farmers' Bull. 

 No. 345 (1908). 



Preservation of Wood by Impregnation. — Impregnation tends to increase the dura- 

 bility of wood by injecting an antiseptic liquid and may mean a desirable, or un- 

 desirable, change of color, and in some cases fire-proofing. Little is known about 

 he latter. Four principles may be applied. 



A. Immersion. 



I. Immersion in a salt. Corrosive sublimate (kyanizing). 



II. Metalized wood by dipping in a solution of iron sulphate. 



B. Boiling. 



I. In salt water or solution of borax. 



II. Frank's mixture, 95 per cent, liquid manure and 5 per cent, of lime. 



III. Injection of copperas (siderizing). 



IV. With exhaust steam. 



