will be apparent from the similarity in the shape of the curves for the different years.

In order to use a fairly large vertical scale so as to make the fluctuations stand out clearly, it was necessary to avoid entirely the zero lines for the curves plotted in Fig. 103. The omission of the zero ^^MM Tonnage engaged in Foreign Trade lines may cause the fluctuations

C=Z1 Tonnage engaged In DomesticTrade from month to month to appear

greater than their true size would

Amounts ia thousands of tons

^

Gross tonnage given for United States Net tonnage giuenfbr United Kingdom

I.

ii

o

oo

-i I

•"Is Si

i

warrant. It is sometimes possible

to plot a chart on the general

scheme of Fig. 103 so as to use zero

lines, but many times it will be

found that the zero lines cannot

be used without adding confusion.

Though it would be preferable to

have the zero lines included, the

gain due to the arrangement of

the curves as shown here for

comparative purposes is great

enough to offset the disadvantage

of not having the zero lines on the

chart.

The zinc plate for Fig. 103 was

prepared directly from typewritten

copy, with no handwork involved

except to make heavier some of

the green background lines and to

draw the actual curves themselves. loi. Comparison since 1850 of the -nt ■• • t;>- tao -i-u -1- -tu ti.

Merchant Tonnage of the United Notice m Fig. 103 that the month