296 



G. R. PUTNAM CONDITION OF THE EARTH S CRUST 



Anomalies 



t 



(in dynes), g observed, — g computed. 



A . 





.2 c 



r= C 



- ~ 



Station. I ■ 



5 -.a 



£ Zz 



+» d 5 



£ * ^s 



S o 



Meters. Dynes. 



Wrangell, Alaska 7 —.039 



Burroughs Bay, Alaska — .097 



Port Simpson, British Columbia 6 — .019 



Seattle, Washington (high school).... 74 — .135 



San Francisco, California 114 — . 017 



Mount Hamilton, California 1,282 —.039 



Hoboken, New Jersey 11 + .008 



Baltimore, Maryland 30 — .034 



Saint Paul, Alaska 12 12 + .033 



Honolulu, Hawaii 6 + . 194 



Mauna Kea, Hawaii 3,981 4- . 244 



Saint Georges, Bermuda 2 + .217 



Jamestown, Saint Helena 10 4- . 209 



For all 42 stations, range . 507 . 765 



Mean, with regard to sign — .060 + .013 



Mean, regardless of sign . 104 . 068 



For first 25, United States stations, range . . . 278 . 316 



Mean, with regard to sign —-.116 — .013 



Mean, regardless of sign . 117 .039 



iJ5 



Dynes. 



— .040 



— .101 



— .017 



— .137 



— .030 

 4-.091 

 + .006 

 —.031 

 + .030 

 + .190 

 + .628 

 + .212 

 + .211 



a 



a 



© d 



% o 



CJD«l© 



~ -oo 



< 



Dynes. 

 + .014 



— .044 

 + .021 

 —.079 



— .047 

 —.030 

 + .008 



— .034 

 + .026 



— .010 

 + .06S 



— .037 



— .045 



7 

 a 





£ 



ft 

 Dynes. 

 + .016 



— .025 

 + .021 



— .095 



— .025 



— .005 

 + .022 



— .013 



— .002 

 + .052 

 + .183 

 + .018 

 + .058 



147 .278 



,006 +.005 



.025 .024 



.086 .062 



.008 —.002 



.018 .014 



A comparison of the average elevation anomalies with those by the 

 Bouguer and free air reductions showed that the large anomalies by either 

 of the latter were eliminated. This is particularly noticeable in compar- 

 ing the anomalies for stations in mountainous regions, and with the free 

 air anomalies for summit stations such as Pikes Peak, Deer Park, Mount 

 Hamilton, and Mauna Kea, and stations below the general level, as Den- 

 ver, Grand Junction, and Green Biver. This average elevation method 

 of 1895 was the first that eliminated the excessive anomalies in moun- 

 tainous regions and on islands. It was based on a theory of general com- 

 pensation, and, as stated, the results confirmed the validity of the equilib- 

 rium, or isostatic, theory of the condition of the earth's crust. 13 The 



12 A correction is applied to the 1805 residuals at Saint Paul to compare with the later 

 observation used in 1912. 



13 American Journal of Science, 1896, p. 192. 



