Page:Popular Science Monthly Volume 88.djvu/261

 Popular Science Monthly

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���These drills, while sinking deep into the ground, constantly send up samples of the earth for examination. They are in the form of solid rods, large or small (as here)

With several soundings thus made in different parts of a property and accurate records kept of the material encountered at different depths, it is a simple matter to map the various underlying strata and eliminate absolutely all guesswork from subsequent operations.

The Size of a Railway Station

LOVERS of statistics will be interest- ed to know that in the concourse of the express level of the Grand Central Station, New York, the old City Hall of that city could be placed with twenty- eight feet to spare at either end and with one foot clear on each side. The top of the statue on the City Hall would be nearly fifteen feet under the ceiling. The number of passengers handled annually at this great station increased from fif- tcn million, seven hundred and fifty thousand in 1903 to twenty million, eight

��hundred thousand in 1914. In 1905, nine hundred and eighty-two thousand cars entered the station, and in 1914 there were one million, one hundred and twenty-six thousand. Fewer trains, however, are entering the station, for in 1905 there were two hundred and seven thousand eight hundred trains, while in 1914 there were but one hundred and eighty-two thousand five hundred. This decrease is due to the fact that more cars are hauled by the electric locomotives in one train than were hauled by the steam locomotives, and therefore fewer trains are required than heretofore.

���Fig. 1

��Fig. 2

��Fig. 3

��Typical cores and how they are procured. Fig. 1 is working through loose material, with a sharp-pointed drill. Fig. 2 is using steel shot to cut through hard rock. Fig. 3 shows the use of water in cutting, also how pebbles are used to break and hold the core preparatory to stopping the work

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