200 THE PARSONS MARINE STEAM TURBINE AND ITS 
to the Otaki, and the decision to install this system in the White Star liners 
Olympic and Titanic was based on the successful results obtained with the 
Laurentic. (Plate 104.) 
The Olympic has now made four round trips and the designed speed of 
21 knots has been exceeded by 4 knot on service and with a low coal con- 
sumption. 
The low speed French Transatlantic liner Rochambeau has a combi- 
nation arrangement of machinery driving four shafts. In this installation, 
two sets of reciprocating engines are installed on the inboard shafts and the 
exhaust steam from each is passed into low pressure turbines arranged on the 
outboard shafts. ‘This vessel has completed her trials very successfully and 
will shortly be put in service. Two ships with similar installations have just 
been put in hand to the order of Spanish shipowners. The Orient Line has 
also a large vessel in course of construction for the mail service between Eng- 
land and Australia, and having an installation similar to the previous three- 
shaft ships. At the present time there are 12 vessels completed and in course 
of construction having installations of this type. The American steam yacht 
Vanadis represents an alternative arrangement of a reciprocating engine and 
low pressure turbines. In this case there are three shafts, the center one being 
driven by a triple-expansion reciprocating engine, arranged to exhaust into 
low pressure turbines on the wing shafts. This installation was the subject of 
a paper read by Mr. Clinton Crane before the members of this Society in 1910. 
The first application of a geared turbine was made by the Parsons 
Marine Steam Turbine Co. in 1897. 
This installation was made for a 22-foot launch and consisted of one 
combined ahead and astern turbine, coupled to a pinion which was arranged 
to drive two gear-wheels connected to two shafts. In this case single helical 
gear was used. 
In 1910 the S. S. Vespasian was fitted with a geared installation of 
turbines. This ship was originally fitted with one triple expansion surface 
condensing engine. 
After carrying out a series of trials with this engine, the engine and con- 
densing plant was taken out and in its place two fast running turbines, 
arranged in series and each driving, by means of a pinion, a double helical 
gear-wheel connected to the line shafting. It should be mentioned that the 
original propeller, line shafting, and thrust-block were left alone. This ship 
has now been in regular commission for 18 months giving splendid results, 
and absolutely no trouble has been experienced with the gearing, although 
the vessel has steamed about 32,000 knots. Further, it is of interest to note 
that there is no appreciable wear on the teeth of either pinion, and the original 
pair being still in use. (Plate 105.) 
