The cotton growing States in America produce annually nearly three million tons of cotton seed. This, until very recently, has been thrown away as a useless incumbrance, but it is now valued at ten or twelve dollars per ton for the cotton fibre which adheres to it, for the oil extracted from it, and for the feed which the refuse furnishes to cattle. The oil--which may be described as neutral--is used very largely for mixing with other oils, many of which bear a large proportion of it without injury to their special properties. There are still, however, cases of enormous waste in many mineral and mechanical industries. Thus, while in many European countries common salt is a government monopoly, and consequently so dear that the poor do not use as much or it as health requires, in others, as in Transylvania, where it is quarried like stone, the large blocks only are saved, the fragments, to the amount of millions of hundred weights, being thrown away.--Bonar, Transylvania, p. 455, 6. One of the most interesting and important branches of economy at the present day is the recovery of agents such as ammonia and ethers which had been utilized in chemical manufactures, and re-employing them indefinitely afterwards in repeating the same process. Among the supplemental exhibitions which will be formed in connection with the Vienna Universal Exhibition is to be one showing what steps have been taken since 1851 (the date of the first London Exhibition) in the utilization of substances previously regarded as waste. On the one hand will be shown the waste products in all the industrial processes included in the forthcoming Exhibition; on the other hand, the useful products which have been obtained from such wastes since 1851. This is intended to serve as an incentive to further researches in the same important direction.] The earth was not, in its natural condition, completely adapted to the use of man, but only to the sustenance of wild animals and wild vegetation. These live, multiply their kind in just proportion, and attain their perfect measure of strength and beauty, without producing or requiring any important change in the natural arrangements of surface, or in each other's spontaneous tendencies, except such mutual repression of excessive increase as may prevent the extirpation of one species by the encroachments of another. In short, without man, lower animal and spontaneous vegetable life would have been practically constant in type, distribution, and proportion, and the physical geography of the earth would have remained undisturbed for indefinite periods, and been subject to revolution only from slow development, from possible, unknown cosmical causes, or from geological action.