Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-08-30

N NDER authority conferred upon the
ILA Navy Department by the act Of Congress
kmaking appropriations for the naval
Nkservice, approved June 80. 1890. plans
~ for a protected cruiser Of about Z 800
tons displacement are now being prepared in
the Bureaus Of Construction and Repair and
Steam Engineering. Proposals have been in
vited under date OF July l. 1890, from all repu-
table builders under two classes as follows:
Class ]. For the construction of the hull and
machinery, including engines, boilers and ap-
purtenances, complete in all respects in ac-
cordance with the plans and specifications pro-
vided by the Secretary of the Navy.
Class 2 For the construction of the hull and
machinery, including engines, boilers and ap-
purtensnces. complete in all respects in
cordance WITH the plans and specifications pro-
vided by the bidder.
No proposal will be considered unless accom-
panied by full and complete specifications of
the hull and machinery by such plans as may
be necessary for a thorough Interpretation of
the design thereof, and by a satisfactory guar
antee Of the results Of the same if adopted
Bidders may, II they desire, adopt the plans
and specifications of the department for the
hull and machinery, or any part thereof, and
embody them in their plans and specifications
10 be submitted with their proposals The
plans and specifications submitted by the bid
ders must. however. conform to the require
ment that all their parts shall be of domestic
manufacture and In compliance with the pro-
visions of the act Of August 8, 1856. The con-
tractor must guarantee an average speed in the
open sea under conditions prescribed by the
Navy Department of n knots per hour,
malntsined for four consecutive hours. during
which the air pressure in the fire rooms shall
not exceed one inch Of water, and for every
quarter knot of speed above the guarantee the
contractor shall receive premium of $4,000
while for every quarter knot that the vessel
fails of reaching the required speed there shall
be deducted from the contract price the sum of
$4,000. The plans now being prepared by the
department. may be seen and examined at the
department on and after the Goth instant The
vessel must be completed within two and one
half years after the contract is signed.
THE PLANS.
The department. plans can for Q vessel 400
feet long on the mean load line; beam nodded
IS feet; draught, mean normal, % feet; ex-
treme normal, "a feet; displacement, normal,
about I, 800 tons; speed sustained Il knots. and
indicated horse power, 20, 500. The main bat
terry consists Of four 6-inch B. L. R. OF high power,
eight 4-inch 3. p rapid firing about eighteen
machine guns and six torpedo tubes The ar
rangement OF the motive power will be some
what novel, as the force will be transmitted
through three screws, one placed amidships az
In ordinary single-screw vessels and two others
placed further forward, one on each side, as is
usual In twin-screw vessels; this arrangement
10 not entirely new, having been adopted by
the French for some of their later vessels but
represent the latest advance in the steam engi-
neering line where such great power is TO be
Transmitted. If twin screws were used over
10000 p. would pass through one shaft now
each shaft transmits only $3.50, and the vessel
has one more chance in case of break down.
The machinery and boilers we're designed by
Engineer-in-Chief Melville, and consist Of
three sets OF triple expansion vertical inverted
cylinder engines. driving the triple screws be-
fore mentioned. the center screw being about
four feet SIX inches below the other two. Each
engine is placed in water-tght compartment
and 10 complete in every respect 30 that the
vessel may be propelled at slow speed by the
center screw alone, by the two outer screws at
q medium speed and by the three screws when
the highest rate of speed is required. Each
shaft Ia fitted with q disengaging coupling 80