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tions in the country at large, in either the near or the distant future. This report has been published as Geological Survey Bulletin 838 and one of the purposes of its publication is as a warning to the public against certain stock promotion enterprises with claims of nitrate deposits as their basis. T. K. C.
Thiokol.-Through the mail comes an announcement of a rubber substitute, Thiokol, which is described as an olefinpolysulfide reaction product.
Although it is carefully pointed out that this synthetic product contains no rubber, it is interesting to recall that rubber essentially is a polymerized olefin and as such readily combines with sulfur in the process known as vulcanization.
Thus, we can expect to find a similarity between the chemical constitutions of Thiokol and vulcanized rubber.
For many uses Thiokol should prove more satisfactory than rubber.
The former exhibits unusual resistance to the deteriorating action of gasoline and oils. Because of this Thiokol tubing can be used to convey gasoline from the tank to carburetor in certain makes of automobiles that require a certain length of flexible piping. Unlike rubber, Thiokol compoupds do not age or deteriorate in storage.
Oxygen does not appear to affect it and even ozone does not cause degradation.
No doubt Thiokol will replace rubber in those applications involving conditions specifically detrimental toward the latter.
T. K. C.