DRESSINGS FOR WOUNDS 165 



compound petroleum oil, containing more or less naphtha and costing 

 about 20 cents a gallon. Melt the asphaltum in a kettle of several 

 gallons capacity. When thoroughly melted withdraw the fire, then 

 add the Varnolene and stir thoroughly until of uniform character. 

 If desired, the vessel may be again heated and uniformity better as- 

 sured. This gives suitable consistency for warm weather and is in 

 the proportion of one part asphaltum to two parts Varnolene by 

 weight. In the winter a preparation of one part asphaltum to 2>4 

 parts Varnolene by weight may be desired. WARNING WHEN 



THE VARNOLENE IS ADDED TO THE HOT ASPHALTUM AN INFLAM- 

 MABLE GAS IGNITES, AFTER THE MANNER OF GASOLINE VAPOR. 



This formula is for asphaltum having a melting point of 285. 

 \Vith asphaltum with a melting point of 200, the proportion of 

 Varnolene may be reduced. 



142. Linseed oil fluid asphaltum. To make a fluid asphaltum from 

 linseed oil, use one part of asphaltum to 1^4 to 2 parts of linseed 

 oil by weight. Heat the asphaltum until liquid, then add the linseed 

 oil as per directions given above. The danger from the formation 

 of inflammable gases is much less with the linseed oil than with 

 the Varnolene, but cannot be entirely overlooked. [Linseed oil 

 costs several times as much as Varnolene.] 



These forms of liquid asphaltum may be prepared and packed 

 in suitable cans for use at any time required. They should be put 

 up in tins and soldered, since exposure to the air will make a slight 

 difference in the consistency. 



143. Asphaltum and sawdust filling for cavities. The difficulties 

 arising from using cement in filling cavities in orchard or shade 

 trees are largely traceable to the rigid character of cement filling. 

 The light color is at times likewise an objection to cement as a 

 material for such filling; it also lacks adaptability for use in swaying 

 branches. For these reasons and others, asphaltum and sawdust 

 fillings, originated and tested by John Boddy, City Forester of 

 Cleveland, Ohio, are recommended by A. D. Selby.* Dry sawdust 

 of any variety and solid asphaltum, such as "Byerlyte" and that 

 used for filling in brick pavements, are used according to the 

 formulae below. The details, briefly stated, are as follows; all ma- 

 terial being designated by volume. 



144. For cavities in swaying branches: i part asphaltum to 3 to 

 4 parts sawdust. Moisten tools in crude oil. 



145. For cavities in trunks: i part asphaltum to 5 to 6 parts of 

 sawdust. Moisten tools with crude oil. Stir sawdust into hot 

 melted asphaltum until desired consistency is reached. Distribute 

 sawdust, as added, evenly over surface of vessel to avoid boiling 

 over. Apply in cavities while still hot. No joints or sheet paper 

 separations are required as in cement fillings. If surfaces of fillings 

 are irregular or lack uniformity of color, coat them with gas tar or 

 liquid asphaltum. 



* Circular ISO, Ohio Agricultural Experiment Station. 



