——— r 
2 SCIENTIFIC BOOKS PUBLISIIED BY 
Francis’ Lowell Hydranlics. 
Third Edition. 
4to. Cloth. $15.00. 
LOWELL HYDEAULIC EXPERIMENTS — being a Selec- 
tion from Experiments on Hydraulic Motors, on the Elow of 
Water over Weirs, and in Open Canals of Uniform Rectangular 
Section, made at Lowell, Mass. By J. B. Francis, Civil Engineer. 
Third edition, revised and enlarged, including many New Ex 
periments on Gauging Water in Open Canals, and on the Flow 
through Submerged Orifices and Diverging Tubes. With 23 
copperplates, beautifully engraved, and about 100 new pages of 
text. 
The work is divided into parts. Part L, on hydraulic motors, includes 
ninety-two experiments on an improved Foumeyron Turbine Water-Wheel, 
of about two hundred horse-power, with rulea and tables for the construction 
of similar motors; thirteen experiments on a model of a centre-vent water- 
wheel of the most simple design, and thirty-nine experiments on a centre-vent 
water-wheel of about two hundred and thirty horse-power. 
Part II. includes seventy-four experiments made for the purpose of deter 
mining the form of the formula for computing the flow of water over weirs; 
nine experiments on the effect of back-water on the flow over weirs; eighty- 
eight experiments made for the purpose of determining the formula for com 
puting the flow over weirs of regulär or Standard forms, with several table» 
of comparisons of the new formula with the results obtained by former experi- 
menters; five experiments on the flow over a dam in which the crest was of the 
same form as that built by the Essex Company across the Merrimack River at 
Lawrence, Massachusetts; twenty-one experiments on the effect of observing 
the depths of water on a weir at different distances from the weir; an exten 
sive series of experiments made for the purpose of determining rules for 
gauging streams of water in open eanals, with tables for facilitating the same; 
and one hundred and one experiments on the discharge of water through sub 
merged orifices and diverging tubes, the whole being fully illustrated by 
twenty-three double plates engraved on copper. 
In 1855 the proprietors of the Locks and Canals on Merrimack River con- 
sented to the publication of the first edition of this work, which contained a 
selection of the most important hydraulic experiments made at Lowell up to 
that time. In this edition the principal hydraulic experiments made there, 
subsequent to 1855, have be*u added, including the important series above 
mentioned, for determining rules for the gauging the flow of water in open 
oanals, and the interesting series on the flow through a submerged Yenturi’s 
tube, in which a larger flow was obtained than any we find recorded.