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in the present case in the broadest sense. He starts out by postulat- 

 ing general isostasy thus making the term nearly equivalent to a uni- 

 versal static conservation. His theme is stated as follows: "Let us 

 postulate that the greatest features of the earth's relief, such as conti- 

 nents and great ])lateaus, are sustained isostatically, and that the small 

 features, such as hills and small mountains, are within the competence 

 of terrestrial rigidity, and then let us inquire what the pendulum work 

 of the Coast Survev has to tell of the status of features of intermediate 

 size, namely the greater mountains and smaller plateaus." 



After describing the methods followed in making the determina- 

 tions the details of the various stations at which pendulum measure- 

 ments were made are discussed. Although the results of the calcula- 

 tions deviate greatly from what would be expected according to the 

 hypothesis of isostasy the measurements are found to be "six times as 

 discordant from the point of view of rigidity as they are from the point 

 of view of isostasy." 



In conclusion it is stated that the " measurements of gravity appear 

 far more harmonious when the method of reduction postulates isostasy 

 than when it postulates high rigidity. Nearly all the local peculiari- 

 ties of gravity admit of simple and rational explanation on the theory 

 that the continent as a whole is approximately isostatic, and that the 

 interior plain is almost perfectly isostatic. Most of the deviations 

 from the normal arise from excess of matter and are associated with 

 uplift. The Appalachian and Rocky Mountains and the Wasatch 

 plateau all appear to be of the nature of added loads, the whole mass 

 above the neighboring plains being rigidly upheld. The Colorado 

 plateau province seems to have an excess of matter, and the Desert 

 Range province may also be overloaded. The fact that the six stations 

 from Pike's Peak to Salt Lake City, covering a distance of 375 miles, 

 show an average excess of 1345 rock-feet indicates greater sustaining 

 power than is ordinarily ascribed to the lithosphere by the advocates 

 of isostasy." Charles R. Keyes. 



Text-Book of Palaeontology. Vol. I., Part i. By Karl A. von 

 ZiTTEL. Translated and edited by Charles R. Eastman, 

 Ph.D. London: Macmillan & Co., Ltd., 1896. 

 An English edition of von Zittel's PaUuvitologie is the most welcome 



of palceontological works that has appeared in a long time. The 



