BOOK V. II. lo-iii. 3 



by 6, because there are 6 sides : the product is 2310. 

 We shall say, therefore, that this is the number of 

 square feet. It will, then, be equivalent to an imcia 

 (A of a iugeruni) less half a scripulum (5^) plus -^ of 

 a scripulum."^ 



III. Having grasped what may be called the first How many 

 principles of this kind of calculation, we shall have plants can a 



T JU T . 1 lugerum of 



no dimculty about entering upon the measurement land con- 

 of pieces of land, with the various kinds of which it fnJgrvals of 

 is a long and arduous task to deal at this point. I three to tan 

 will now also add, in addition to those which I have '^^ ^^^"^ ' 

 already set forth, two rules which husbandmen often 

 employ in the setting out of plants. 



Suppose that you have a piece of land 1200 feet 

 long and 120 feet wide, in which vines have to be; 

 so arranged that five feet are left between the rows. 

 How many plants, I ask, are necessary when spaces 

 of five feet are required between the plants. I take 2 

 a fifth of the length, which makes 240, and a fifth of 

 the breadth, which makes 24. To each of these 

 numbers always add one unit, which forms the 

 outermost row, and which they call the angular row ; 

 one number, therefore amounts to 241, the other to 

 25. Multiply these figures as follows : 25 times 

 241 makes 6025. This, you will say, is the number 3 

 of plants required. 



Similarly, if you wish to set them six feet apart, 

 you will take a sixth of the longitude (which is 1200), 

 that is 200, and a sixth of the breadth (which is 120), 

 that is 20. To each of these figures you will add 

 what I called the angular units. The numbers are 



" Y^ of a iugerum = 2400 square feet : half a scripulum = 

 50 square feet : -[\ of a scripulum — 10 : therefore 2400 — 60 

 = 2340 square feet. 



23 



