_Lecture_ 7.--Gauging of the volumes and valuation of the dynamical power of water-courses which feed machines. SECOND SECTION.--MOTOR MACHINES. _Lecture_ 8.--Theory of the effect of water on hydraulic wheels. Determination of the elements of the calculation. _Lectures_ 9 to 13.--Application of the general theories to the principal hydraulic recipients. Conditions of the maximum, relative to the useful effect of each kind. Results of experiments, &c. (With reference to turbines, those which are most generally employed in the artillery workshops must be adverted to.) _Lecture_ 14.--Comparative abstract of the usual properties of various hydraulic “recepteurs.” Operations that must be carried on in order to arrive at their results and to their reception in manufactories. _Lecture_ 15.--Physical ideas relative to the use of the vapor of water as a motive power. Theoretical bases of the calculation of the effects of steam-engines. Force exerted by the compression and expansion of elastic fluids. _Lectures_ 16 to 18.--Practical notions and results of experiments relating to the effects and to the usual properties of the principal systems of steam-engines in use, as to the employment, reception, and maintenance in workshops. THIRD SECTION.--RESISTANCE OF MATERIALS. _Lecture_ 19.--Resistance to compression: 1st, by gradual pressure; 2d, by shock. Results of experience. Application to wooden and cast-iron supports, and to the foundations of machines. Stocks of hammers. _Lecture_ 20.--Resistance to traction. Application to the shank of a piston, to bolts, chains, cordage, and leather straps. Resistance to flexure. Practical formulæ for calculating the transverse dimensions of the wooden or cast-iron arms of hydraulic wheels, of the catches or sails. _Lecture_ 21.--Continuation of the resistance to flexure. Practical formula for calculating the dimensions of the several parts of such machines. Cranks, winches, and handles in wood or in metal. _Lecture_ 22.--Resistance to torsion. Practical formulas. Results of experiments relative to the resistance of wood and metals to boring and turning. Resistance of cast-iron plates to clipping. FOURTH SECTION.--WORKING MACHINES _Lectures_ 23 and 24.--Of blowing machines. General expression of their useful effect. Conditions of the maximum effect. Ventilators; their use in workshops and galleries of mines. Practical bases of their construction. Blowing machines with a piston. Description. Calculation of the effects and results of experiment. _Lectures_ 25 and 26.--Description and properties of alternative and circular sawing machines. Practical rules for their establishment. Results of experiments concerning the motive power they require, the useful effect obtained, and the resistance of various kinds of wood to the action of the tool. Results of observation relative to the work in shops by hand-saws.