rs. Judging
the future development of aircraft by what has taken place in the last
two years, we may look for the building of a 5,000-horse-power airplane,
possibly within a year.

If the people of the various cities along the eight great air-ways
already proposed insist on it, at least a dozen additional aerial mail
lines can be established within twelve months. This can be done by
utilizing only machines not needed by the army or navy. That means it
will be possible to send by postplane at least 50,000,000 of the
100,000,000 day and night letters, and at least 25,000,000 of the
50,000,000 special delivery letters that are sent each year in the
United States.

Postoffice officials estimate that the average cost of telegraphic day
and night letters now going over the wires is close to one dollar each.
Special delivery letters average about thirteen cents apiece.

This makes a total of more than fifty million dollars' worth of
potential aerial mail business that is simply waiting for the
establishment of aerial mail routes which can easily be established
within the next twelve months.

Four hundred miles is the distance over which postplane day mail is most
effective. Aerial mail letters are effective over any distance, since,
with proper stations, light signals and guides for night postplane
flying, the air mail can be carried more than one thousand miles between
the hours of 6 P. M. and 8 A. M.

The cost of aerial mail night and day letters will be less than that of
wire communication. The cost of an aerial mail letter is sixteen cents
for two ounces. For this price there can be sent a message that would
cost five dollars to send by telegraph.

The estimate of $50,000,000 of potential postplane business takes no
account of the possibilities of transporting parcel post aerial mail.
One of the Caproni 2,100-horse-power machines now in operation could
easily transport 2,500 pounds of mail. At least $25,000,000 worth of
parcel post could be sent by airplane.

Enthusiasts who look forward to the transatlantic transportation of
aerial mail as certain to come within the next twelve-month assert that
there is another twenty-five million dollars' worth of transatlantic
mail waiting for an aerial mail service. They point out that Uncle Sam
now pays eighty cents a pound to American steamships to carry
transatlantic mail and that a charge of one dollar per letter across the
Atlantic would be a paying proposition.

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