In practical measurements of rooms, deductions must be made from the cubic space for the furniture contained in it and for its inmates. About 10 cubic feet ought to be allowed for each bed and bedding, and 2½ to 4 cubic feet for each individual. Projecting surfaces must be allowed for by subtraction, and recesses by addition. _A circular ward with a diameter of 36 feet has a dome-shaped roof, the height of whose centre is 18 feet. The height to the dome is 12 feet. Find the floor-space and total cubic contents. How many patients ought the ward to accommodate?_ Area of floor-space = (36)^2 x ·7854. = 1017·8784 square feet. Cubic capacity of cylinder below dome = 1017·87 x 12 = 12214·5 cubic feet. Cubic capacity of dome = 1017·87 x 2∕3 x 6 = 4071·48 cubic feet. Total cubic capacity of the ward = 16285·98 cubic feet. Assuming that 1,500 cubic feet are required for each patient, then the ward is large enough for 10 _patients_. It is well to test this conclusion by calculating whether sufficient floor-space has been allowed for each patient. The floor-space has been found to be about 1,018 square feet, which would give 100 feet for each of 10 patients and more than the minimum standard previously stated. _What number of people should be allowed to sleep in a dormitory 40 feet long, of which the accompanying sketch is a section?_ [Illustration: Outline of rectangular space with triangular roof] The cubic capacity of the quadrilateral space below the roof = 16 x 9 x 40 = 5,760 cubic feet. Area of floor = area of base of roof = 40 x 10 = 640 square feet. Cubic capacity of roof = 640 x 1∕3(13 - 9). = 853·3 cubic feet. Total cubic capacity of dormitory = +6613·3 cubic feet.+ If we take the low standard of common lodging houses and allow 350 cubic feet of space for each inmate, then 18 _persons_ may be allowed to sleep in the dormitory. _How much space would a man occupy supposing him to weigh 175 lbs.? How much is usually allowed for a man with his clothes, bed and bedding?_ The space occupied by a man is stated by Parkes to be from 2½ to 4 cubic feet (say 3 for the average). He gives the following rule: The weight of a man in stones divided by 4 gives the cubic feet he occupies. Thus, a man weighing 175 lbs. would occupy 3-1∕8 cubic feet of space. About 10 additional cubic feet must be allowed for clothing, bedding, and bed for each person. _What size of inlet and outlet aperture should be allowed per head? How large should each individual inlet be made? If an inlet aperture 100 square inches in area is divided into four, with apertures of 25 square inches each, what is the loss by friction?_ A size of 24 square inches per head for inlet and the same for outlet meets common conditions.