Material. Resin, beeswax, rendered beef tallow, raw linseed oil, white resin, alcohol, turpentine, Burgundy pitch, red ocher, white pitch, Venetian red, No. 16 white knitting-cotton.

Apparatus. Granite kettle, small pail, cooking-burner.

Grafting-waxes are used for the protection of wounds and for the covering of wounded surfaces when certain kinds of grafts are made. Grafting-waxes are made by the following methods:

Beeswax And Resin Waxes

Formula 1. Weigh out one pound of resin, one half of a pound of beeswax, and one fourth of a pound of rendered beef tallow. Place the ingredients in a granite or an iron kettle and allow them to melt, then boil for about one minute, or until the mass is thoroughly mixed. Remove from the fire, and pour the melted mass directly into a pail of cold water. When the mass is cold enough to handle, gather it into a ball and work it with the hands until it assumes a light-brown color. Grease the hands thoroughly with tallow before working, to prevent the wax from sticking to them. Why is the melted wax poured into the water? What is the purpose of the molding and working with the hands? It is important that pure beeswax be used and not wax which has been adulterated with paraffin. Why? Does the wax aid in the healing of a wound? Discuss.

Formula 2. Weigh out one pound of resin, one fourth of a pound of beeswax, one fourth of a pint of raw linseed oil. Place the ingredients in a granite kettle and allow them to melt gradually. When the mass is thoroughly melted and incorporated, pour it into a bucket containing cold water, and treat as above. After twenty-four hours examine both batches and describe fully the differences, if any. Explain.

Grafting-cord. Often in the making of root grafts and occasionally in budding, grafting-cord is needed. This is made by securing a ball of No. 16 knitting-cotton and placing it in the kettle of melted wax of Formula 1. Allow the ball of cotton to remain in the melted wax for at least five minutes, or until it is completely saturated. The ball should be turned frequently, in order to insure complete saturation. When finished, allow it to cool, and wrap in oiled paper for future use.

Why is cord prepared in this way superior for grafting purposes to the ordinary wrapping-twine?

Alcoholic Waxes

Formula S. Weigh out one and one-half pounds of white resin and one fourth of a pound of beeswax. Place the ingredients in a granite kettle and heat them until they are thoroughly incorporated. Remove the mass from the fire and stir until partially cooled. Now gradually add enough alcohol to give to the mass, when cooled, the consistency of thick paint. Describe the color and the appearance of this wax and tell where it can best be used.

Formula 4. Weigh out one-half pound of white resin and one-half ounce of rendered beef tallow. Heat the two substances together until they are incorporated. Remove from the fire, cool, and add one teaspoonful of turpentine. Stir the mass until thoroughly mixed, and gradually add enough alcohol to make the mass assume the consistency of thick honey. (From six to eight fluid ounces of 95 per cent alcohol will usually be sufficient.)

What are the differences between formulas 3 and 4? Describe the appearance of the two waxes, and give your opinion as to which is the best.

Pitch Wax

Formula 5. Weigh out twelve ounces of resin and six ounces of Burgundy pitch and melt them together in a granite kettle, stirring thoroughly. At the same time melt three ounces of rendered beef tallow in another vessel. Pour both liquids together while hot, and stir thoroughly. To this mass add four or five ounces of red ocher, and stir the mixture until it is smooth and until the different ingredients are completely incorporated. Describe the mass and tell when and where it should be employed.

Note. The linseed oil should be entirely free from cottonseed oil.

These grafting-waxes may be made by groups of from two to four students.