591.1 89 
ii 
Some More Rowing Experiments 
N the autumn of 1895 the author designed an indicator for 
recording the work done in a stroke of rowing.’ The apparatus 
replaced the front thowl of the rowlock, and consisted of a plate 
turning with the oar, which pressed against it, about an axle to 
which it was connected by means of another plate pivoted to the 
first, 
The pressure of the oar tended to move the front plate back 
towards the axle, this motion being resisted by a spring. The 
movements of the plate, and consequently of the oar, were recorded 
as a diagram on a horizontal card by a pencil connected with the 
plate. This diagram afforded the information given by the familiar 
steam-engine indicator diagram, and gave measures of the horse- 
power of oarsmen, as well as interesting information with regard to 
the way in which the work was done, showing the great differences 
that existed between the style and stroke-forms of different oarsmen. 
The successful working of this simple instrument encouraged 
the author in 1896 to attempt another, obviating the shortcomings 
of the first. This latter, in addition to various mechanical imperfec- 
tions, had the disadvantage of giving the diagram in curvilinear 
co-ordinates, necessitating Jaborious measurement and _ reduction 
before stroke form and work done could be estimated. 
Further, in testing a steam-engine it is customary to take 
several diagrams during a run, by changing the card on which 
the figures are being drawn. In a boat this is impracticable 
without stopping the rowing. It will be seen that an important 
part of the later machine is the automatic winding apparatus, where- 
by the card changes itself. The author was recently interested in 
having his attention called to a similar device which was being 
introduced for the steam engine. 
The general principle of the former indicator, that of recording 
the movements of a plate turning with the oar and pressed forward 
by a spring, has been adhered to, In the photographs (Plate I.) 
and diagram illustrating the action of the pencil and spring (Fig. 1) 
the face A moves with the oar, and is connected with the axle B 
1 For a description of the instrument and results obtained, see Natural Science, vol. 
Vili., pp. 178-185, March 1896. 
G 
