CHAPTER XIII.                            149

that in which all three pddas have the smallest pos¬
sible number of syllables, i.e. 4 -f 4 + 16,

"The right-side number and the middle number we
write down as we have done with the pddas of the two-
pddoj metre, and we make with them the same calcula¬
tion as we have done above. Besides, we add the left¬
side number in a separate column, but do not make it
undergo any changes.    See the following scheme:—
 

4
 

4
 

16
 

4
 

5
 

15
 

4
 

6
 

14
 

4
 

7
 

13
 

4
 

8
 

12
 

4
 

9
 

II
 

4
 

10
 

10
 

4
 

II
 

9
 

4
 

1.2
 

8
 

4
 

13
 

7
 

4
 

14
 

6
 

4
 

15
 

5
 

4
 

16
 

4
 

"This gives the number of 13 permutations, but by
changing the places of the numbers forwards and back¬
wards in the following method, the number may be
increased sixfold, i.e. to 78 :—

" I. The right-side number keeps its place ; the two
other numbers exchange their places, so that the middle
number stands at the leftside; the left-side number
occupies the middle :—
 

1.
 


 

1
 


 


 

4
 

4
 

16
 


 

5
 

4
 

15
 


 

6
 

4
 

14
 


 

7
 

4
 

13 &c.
 

"II.-III. The right-side number is placed in the
middle between the other two numbers, which  first