Plotted from Records of the United States Signal Service and of Blodgett's Climatology of the United States

Information for eight different cities is so given that comparisons are easily made. Note the different Hncs used here instead of colors. Since Pittsburgh was the city under prime consideration, the Pittsburgh line was made heavy ttiat it might be most clearly seen. This chart gives a great amount of data in smaller space than would be required to show the facts by any method other than the use of curves

COMPARISON OF CURVES

broken oflf, most readers will not imagine correctly the great height to which that peak would extend if it were shown in full. The chart could have been greatly improved if the upper portion of the peak had been drawn in full size horizontally as though hinged near the upper margin of the drawing. Since the full height of the peak is

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March, 1913 ■ March. 1913

Engineering Reeord

Comparison of Flood Rise in Two Rivers in New York State During the Floods of March, 1913

In the preceding illustrations of this chapter there has been such similarity in the shape of the curves considered that they were superimposed for comparison. Here the curves are of different shape and they are shown in separate fields so that the contrast may be more striking. The chart at the left should have had the zero line shown. It is dangerous to base conclusions on the comparison of two curves unless the zero lines are shown in each case