EXPERIMENTS ON THE FROUDE. 
By C. H. PEaBopy, MEMBER OF COUNCIL. 
{Read at the eighteenth general meeting of the Society of Naval Architects and Marine Engineers, held in 
New York, November 16 and 17, 1911.] 
The inception of these experiments was due to the late Dr. Charles G. 
Weld, of Boston, a representative of an old New England family of ship- 
owners and an enthusiastic yachtsman. He conceived the idea that there 
are certain distinct advantages in making experiments by the aid of navigable 
models, on the resistance and propulsion of ships, and undertook to provide 
the means, while intrusting the execution of his ideas to the writer. The 
preparation of the model and its machinery and the prosecution of the 
experiments have been made by the staff of the Department of Naval 
Architecture and Marine Engineering of the Massachusetts Institute of 
Technology. 
The prototype chosen for investigation was the Revenue Cutter Man- 
ning which was tested by the writer under favorable conditions in 1899.* 
The model was made one-fifth of the length of the Manning; the main 
dimensions of the prototype and the model are :— 
Manning. Froude. 
Length between perpendiculars, feet.... 188.0 37.60 
Moulded beam) feet)... .....5....2--> 32.0 6.40 
Mean dratteht, feet... i... 5 be ee TA. 252 
Displacement tonsa. oe: as hea sci e & 1,000.0 8.00 
Wetted surface, square feet............ FANG 296.00 
Diameter propeller iieete no. 4 an TiO 2.20 
Pitchapropeller teeta seers cis otras. 1238 2.47 
Projected area of blades, square feet.... 31.4 6.28 
Though properly called a model, our craft, which was named the Froude 
is a miniature steamer of considerable size and displacement, which handles 
and behaves like a ship, and not at all like a steam launch. 
Fig. 1, Plate 35, gives the lines of the Froude and Fig. 2, Plate 36, gives 
the inboard profile, showing the general arrangement of the machinery and 
apparatus. 
*Transactions Society Naval Architects & Marine Engineers, Vol. 7. 
{In fresh water. 
