Scientific American Supplement, No. 611, September 17, 1887 | Page 4

were weighed out under the supervision of
the officers of the company, who also took the record of speed and
other data. After running down Channel for a considerable time, the
trial on the coals weighed out began, and lasted 4 hours 10 minutes,
during which time 10,885 lb. of Welsh coal were burned, the trial
ending with the same revolutions of engines and the same pressure in
boilers with which it began. The mean indicated horse power,
calculated from the mean of seven sets of indicator cards, taken during
the trial, and the mean revolutions per minute, found by dividing the
total revolutions recorded on the engine counter by the minutes in the
period of the trial, amounted to 2,124, thus making the consumption
1.23 lb. per indicated horse power per hour, and the power per square
foot of fire grate almost exactly 19 indicated horse power. While
testing the indicated horse power and consumption of coal, the steamer
ran to and fro between the Cloch and Cumbrae lights, and also made
several runs on the measured mile at Skelmorlie, from which the mean
speed of the vessel was found to be 14.12 knots per hour. The
remarkably high results obtained were most satisfactory to the
representatives of the owners, and a large party of experts on board
congratulated Mr. Howden on the successful fulfillment of the onerous
guarantees undertaken.--_Engineering._
* * * * *

THE CEARA HARBOR WORKS.
The works illustrated by the engravings are now being constructed
under a concession from the imperial government of Brazil. The
province of Ceara has an area of about 50,000 square miles, and is one
of the richest in Brazil. Its produce comprises sugar, coffee, cocoa,
cotton, tobacco, spices, fruit, cabinet and dye woods, India rubber, etc.
Its population at the last census, taken in 1877, amounted to 952,624

inhabitants, that of the capital, the city and port of Ceara, being about
40,000. Although Ceara is the principal seaport at which lines of
English, French, American, Brazilian, and other steamers regularly call,
prior to the commencement of the harbor improvements it was almost
an open roadstead, passengers and goods having to be conveyed by
lighters and boats between vessels and the shore. The official statistics
of the trade and shipping of the port show that an income of £35,750
per annum will be collected by the Ceara harbor corporation from the
dues which they are authorized by their concession to charge on all
imports and exports and on the vessels using the port and from the rent
of the bonded warehouses.
[Illustration: NEW HARBOR WORKS, CEARA, BRAZIL.]
The drawings given here show the nature of the works, which are of a
simple character. The depth of water along the principal quay, which is
being constructed of solid concrete, and is connected with the shore by
an iron and steel viaduct over 750 ft. in length--which is already
completed--will be 19 ft. at low water and 25 ft. at high. This quay and
breakwater is shown in perspective, in plan, and in section, and is of a
very heavy section, as will be gathered by the scale given immediately
below it. Meanwhile the landing of cargo is temporarily carried on at
the end of the viaduct, which at high tide has a depth of about 20 ft. of
water. The custom house and bonded warehouses are being built of the
fine granite obtained at the Monguba quarries, which adjoin the
Baturite railway, about sixteen miles from the port. A new incline has
also been constructed from the rail way down to the port. The line has
been laid along the viaduct, and will be extended over the quays as
soon as they are completed. The concrete, of which a large quantity is
being used, is mixed by Carey & Latham's patent mixers, and the
contractors have supplied the very large and complete plant for
carrying out the operations.
The engineer to the corporation is Mr. R.E. Wilson, M. Inst. C.E.,
Westminster, and his resident at Ceara is Mr. R.T.H. Saunders, M. Inst.
C.E. The contractors for the work are Messrs. Punchard, McTaggart &
Co., their representative at Ceara being Mr. George Wilson, M. Inst.

C.E._--The Engineer._
* * * * *

ELECTRIC STREET RAILROADS.
BY GEORGE W. MANSFIELD.
Why should we prefer electricity as the propelling agent of our street
cars over all other known methods? I answer, without hesitation,
because it is the best, and being the best is the cheapest. Briefly I will
present the grounds upon which I take my stand.
To-day the only methods for tramway service are three in number:
Horses, with a history of fifty years and over; cables, with a history of
fifteen years; and electricity, with a history of two years. I give the