524 



HENDEBSON'S HANDBOOK OF PLANTS 



Contents of a Round Cistern in Gallons and 

 Number of Bricks required for each foot 

 in Depth: 



A circle encloses the largest space of any 

 figure for the same length of line. A circular 

 cistern is therefore the cheapest. The fol- 

 lowing table gives the differences of 

 Area of Square and Round Cisterns. 

 Squabe. 

 Diameter Length of Wall. Area of Surface. 



Sfeet 32feet. 64 square feet. 



10 " 40 ■• 100 ■■ 



12 " 48 " 144 " 



Diameter. Lengtli of Wall. Area of Sarface. 



lOfeet 31^feet. 78>i equaie feet. 



12 " 37M '■ 112 " " 



16 •• 47 " 117 



Twice the diameter of a circle or a square 

 gives four times the area in square feet ; twice 

 the diameter of a cube gives eight times the . 

 solid contents in cubic feet ; half the diameter 

 gives one-fourth of the area, or one eighth of 

 the cubic contents. 



■Well Digging. Quantity of earth excavated 

 for each foot in depth of different diameters : 

 3 ft., 261 cubic yards; 3 ft. 3 in., 307 cubic 

 yards ; 3 ft. 6 in., 356 cubic yards ; 4 ft., 465 

 cubic yards; 4 ft. 6 in., 589 cubic yards; and 

 5 ft., 727 cubic yards. 



Weight of Timber. English oak weighs 50 

 lbs. to the cubic foot; American oak, 47; 

 Baltic, 46 ; mahogany, Honduras, 40 ; and 

 Spanish, 55; larch, 35; ash, 50; birch, 48; 

 beech, 51 ; elm, 39 ; poplar, 32 ; red pine, 40 ; 

 yellow pine, 33; Danzic fir, 35; and Memel 

 fir, 38 lbs. to the cubic foot. 



WEI&HTS AND MEASIJKES. 



Table for Converting Sundry Weights and Measures 



Into the Metric System, and the reverse ; constructed on the basis of the tables published in the 

 Smithsonian Keport for the year 1865, prepai'ed by Henry G. Hanks. 



The above table will be found to meet all the requirements of the assayer and chemist. The following example will 

 explain its use : Suppose the capacity of a tank or cistern is found by measurement to be 82 cubic feet, and the number 

 of Uters is required. Befer to table No. 2, and find that 8 cubic feet = 226.54 liters. Eigllty cubic feet will be ten times 

 as much. Therefore : 80 cubic feet = 2265.40 liters. 



2 cubic feet = 66.63 liters. 



Metrical or Modern System: 



Trench. 

 Millimetre, 

 Centimetre, 

 Decimetre, 

 Metre, 

 Decametre, 

 Hectometre, 

 Kilometre, 

 Myriametre, 



LINEAB HEASTTBB 



Metre. 



.001 



.01 



.1 



1 



10 



100 



1000 



10,000 



or .039371 inches. 



or .39371 



or 3.9371 



or 39.371 



or 393.71 



or 3937.1 



or 



or 393710 



or ^ mile, 

 or 6^ mile^. 



The basis or unit of the system is the inetre, 

 which is the ten-millionth part of the terres- 

 trial arc from the equator to the pole, and the 

 length of which in English measure is 1.0936 

 yards, or 3.2809 feet, or as above in Inches. 

 By mulHph/mg the metre respectively by 10, 

 100, 1,000 and 10,000, we obtain the deca, kecto, 

 kilo and myria metre respectively; and by 

 dividmg the metre by 10, 100 and 1,000, we ob- 

 tain the ded, cenli andrnMi metre respectively. 



