 516  175. The geologists teach us that coal has been formed millions of years ago from the enormous quantities of vegetation and trees. The process of their decay must have been very gradual but constant. 176. Although vasoconstriction does not enhance body insulation by an order of 10 in man (or other land warmblooded animals) upon cold exposure, it does assist in maintaining a degree of thermal insulation in the face of exercise and shivering and thus helps to conserve body heat. 177. Air cooling instead of water cooling would also reduce the weight of the engine, but a larger blower (fan) would be required to keep the engine cool. Power to drive this blower would have to come from the engine itself, therefore reducing the power output and at the same time increasing the fuel consumption. 178. Each time a piece of magnet is broken, each fragment upon being tested with a compass is found to have a north pole on one end and a south pole on the other. 179. Lubricants are employed in engineering practice for two reasons: to diminish friction surface of machine parts, and to diminish friction between a cutting tool and the material being cut, and at the same time serve to dissipate the heat developed in the operation. 180. The effect of the pumping field will be to change the radius and phase of the orbit in a manner depending on the value of 0Q. Strictly speaking the axial velocities will also be changed, but this effect will be ignored for the time being. 181. It is the object of this paper to extend the theory to the large-signal region, taking into account the variation of axial velocity, the change in total energy due to the electrostatic pump potential and the true form of the twisted quadruple field. 182. It was early recognized that all the rocks were surprisingly similar in chemical composition, the fact having been confirmed by the subsequent examination of rocks from different parts of the world. 183. In the usnolic acid series, spirans (I) are attacked by ozone in the expected fashion to give coumaranones (II), but in the grisan series ozonolysis (in methyl acetate) of spirans (III) gives anomalous results, the products having been assigned structures of type (IV). 516 |
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