le ended boiler 12 feet 9 inches diameter and fifteen
feet long, having a total heating surface of 2,270 square feet, and
identical in design with the boiler supplied for the other engines. The
propellers were made exactly alike in all respects, and the ships being
likewise precisely alike, a comparison of the performances of the one
fitted with the triple engines could be made with as little grounds for
differences of opinion as is possible. One of the ships fitted with the
ordinary compound engines was named the Kovno, that with the triple
compound engines the Draco. Their dimensions are as follows:

Feet. Inches.
Length between perpendiculars. 270 0
Breadth. 34 0
Depth of hold. 18 3

And of 1,700 tons gross register. They are ordinary cargo boats, built of
steel, having a raised quarter deck and long bridge amidships, but
nothing about them otherwise requires comment.

After making a voyage or two to the Baltic, and finding that everything
was working satisfactorily, the Kovno was loaded with 2,400 tons dead
weight, and sailed in January, 1883, for Buenos Ayres; the Draco was
loaded with 2,425 tons dead weight, and sailed March, 1883, for Bombay,
the distance in both cases being about 6,400 miles. It was thought
advisable, for purposes of comparison, that the ships should steam at as
near as possible the same speed; and to attain this object, we considered
the safest plan was to instruct the engineers as to the average amount of
coal they were to burn per day, and experience with these ships on their
Baltic voyages had fixed this at 12 tons in the case of the Kovno and 10
tons in the case of the Draco. During the voyage each ship seems to have
had fair average weather, and equal care was taken in getting the best
results possible. The average speed of the Draco was, however, 8.625
knots, or 207 miles per day, the engines making on the average 57.5
revolutions per minute, while the Kovno did only 8.1 knots, or 194 miles
per day, the engines making 55.5 revolutions. The coal used was ordinary
South Yorkshire, just as it comes from the pits for bunker purposes. The
indicated horse power in each case would average about 600. The total
coal consumed was 326 tons in the Draco and 405 tons in the Kovno, or a
saving of 19.5 per cent. over the ordinary compounds, with an increase of
speed of 6.5 per cent.

In December, 1883, one of