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^r MODEL 43
VARICORD LINEAR/LOG LAB RECORDER 24 calibrated ranges from 10 MV or lO^uA full scale. Potentiometric recording, both linear and logarithmic. Absorbance scale zero to infinity.
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MODEL 44
MICROCORD SUPER SENSITIVE LAB RECORDER V2 MV full scale maximum sensitivity, or 50 microvolts per inch. Fast pen speed; excellent noise rejection. Dual chart speed. Write for
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ANALYTICAL CHEMISTRY
use of it from a ship under the hazards of oceanic conditions—waves, currents, and storms. High earth temperatures and pressures, as well as tough rock, will have to be combatted. Probably one of the biggest payoffs of the Mohole Project will come from the geophysical measurements which are planned to be made in the holes. Heat-flow data, together with data on the thermal properties of the rocks, may provide important information bearing on the existence, magnitude, and effectiveness of convection currents in the oceanic crust. Determination of remanent magnetism and shifts in its orientation with depth (and thus with time) should have an important bearing on conclusions on continental drift and on polar migration. Radioactivity determination, together with heat-flow measurements, could provide critical information on the Earth's thermal status and the source of its internal heat. Radioactive age dating of the deep crust and Mantle rock might check the possibility that portions of these represent the original surface of the earth. The direct measurement in a borehole of velocities, densities, and other physical and chemical properties of rocks deep in the Earth should provide a much more reliable basis for conclusions on the Earth's constitution, history, and evolution, than is possible from the present inferences based on indirect geophysical or geochemical interpretation, which may not be able adequately to take into consideration the effect of complex interrelations of these properties at high temperatures and high pressures under natural deep earth conditions. Such data may even have important bearing on conclusions on the character of bodies in space. It is planned to leave instruments in the holes permanently for recording seismic disturbances, magnetotelluric phenomena, etc. Means might also be developed to check the presence and character of fluid emanations from crustal and mantle rocks which might bear on theories of the origin of the oceanic waters and the terrestrial atmosphere. ENDB
