. The Popular science monthly . Photo, C. R. Toothaker, Phila. Commercial Buildings, Trinidad. The hydrocarbons and their derivatives which are insoluble havebeen called asphaltenes. The malthenes of Trinidad asphalt are distinguished by the fact thatthey are of an extremely sticky and cementitious nature, and notmerely oily as is often the case with material of similar consistencyprepared from petroleums. The value of any bitumen or combinationof bitumens for highway construction depends on the character of themalthenes of which it is composed, and the relative proportion of
. The Popular science monthly . Photo, C. R. Toothaker, Phila. Commercial Buildings, Trinidad. The hydrocarbons and their derivatives which are insoluble havebeen called asphaltenes. The malthenes of Trinidad asphalt are distinguished by the fact thatthey are of an extremely sticky and cementitious nature, and notmerely oily as is often the case with material of similar consistencyprepared from petroleums. The value of any bitumen or combinationof bitumens for highway construction depends on the character of themalthenes of which it is composed, and the relative proportion of theseto the asphaltenes. Where the former are not present in sufficientamount, it is necessary to add to the asphalt material in which malthenespredominate to attain a proper consistency. This is known as fluxingthe asphalt, and in the case of that of Trinidad, owing to the presenceof the large amount of malthenes of a sticky nature, it can be accom- 32 THE POPULAR SCIENCE MONTHLY. Photo, C. R. Toothaker, Phila. Commercial Quarters, Point dOr. plished by the use of any of the fluxes that are available, even those of aparaffine nature, since the paraffine hydrocarbons, containing a con-siderable per cent, of paraffine scale, combine with the malthenes of theTrinidad asphalt to produce a satisfactory binding material. If themalthenes were not present to the extent in which they are found, itwould be necessary to use an asphaltic flux, as for example in fluxingthe harder bitumens, such as gilsonite and grahamite. While the malthenes give to the asphalt its cementitious property,the asphaltenes impart cohesiveness as distinguished from adhesive-ness, and supply body and stability to the binding material. It hasbeen found that asphalt cement, that is to say, a solid asphalt combinedwith a suitable flux, must contain not less than 15 per cent, of asphal-tenes or will otherwise lack cohesiveness and stability, while on theother hand, if it contains less
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