Show new apparatus probes into earths core permits the study of minerals under pressure cambridge mass the searching eye of science will be able to t tell about conditions approximately 20 miles below the earths surface with the aid of apparatus newly developed dei eloped at harvard university use of the he apparatus for the first time Is announced by the stall staff of the bordo n mckay and dunbar physics labora laboratories the equipment may reveal hitherto unknown properties of rocks deeper down in the earth thane than carf can be reached by digging italio Is expected to td aid ln in attaining accurate interpretation of seismological and gravitational observations vii vat ions an tl permitting the examination of minerals c under a pressure bres sure of atmo aarno about 75 tons per equale inch com binca with temperatures as hh as COO degrees decrees centigrade the apparatus was devised by drs frands francis birch F cli and K R n R law research associates ailt in geophysics heretofore scientists have been able to only the effects on minerals of high temperature alone or of blab pressure alone whereas a joint study wll wil now be possible two methods ot of abt obtaining bining the combination of high tempera ture fure and pressure have been used the first employs a steel pressure chamber about the size of a pop bottle which lin has s a hole of half inch diameter bored along its axis into this hole Is illse inserted i the specimen a small c ci I under inder of the anin mineral a quarter luch inch in diameter dla two to five inches long the ri neck ci 6 of the pressure chamber Is connected connect eat to a piston capable of compressing nitrogen gas to a pressure of atmospheres then the compression chamber Is placed in an electric furnace and heated as high as centigrade the makes it possible to attain temperatures as high as 1000 centigrade in this apparatus the pressure range Is at present limited to atmospheres heat Is s applied electrically within the pressure chamber and the other walls of the chamber aie are cooled in all their heat beat pressure experiments Ir harvard arvard physicists have found that the best bes t substance tor for transmitting fit the e pressure Is the inert gas nitrogen tro ft |