Let us therefore take the figures which the trees Nos. 4, 12 and 
20 have given in the two years. 
These trees were tapped in both years in nearly similar weather 
conditions, a factor which must be considered if we wish to make 
just comparisons. 
The number of incisions, as was the case in both years, was not 
precisely the spme, but this small difference cancelled the drawback 
of the unfavourable method of tapping. 
Number of Tree. 
1901. 
1902. 
4 1 
12 
20 
4 
12 
20 
Height of tapping 
M. 
330 
2 ‘59 
3’67 
i‘5 
i*5 
i-5 
Surface tapped 
M. 2 
3‘65 
277 
4*50 
i*9 
17 
20 
Total lengths of incisions 
C. M. 
354 
301 
405 
320 
320 
320 
Total yield 
Grs. 
792 
713 
958 
810 
780 
230 
Yield per M. 2 of tapped surface 
Grs. 
217 
257 
213 
426 
459 
615 
The above figures speak for a tapping of the tree to a height of 
1 '5 metre. 
In the year 1901, the question arose whether it was not more 
advantageous to make fewer and longer incisions than more and 
short ones. 
The trees 13, 14, 19 and ;0 of 1901 were tapped as high as 
possible and the incisions made 20-30 c.m. long. 
In the following year 1902, the trees were tapped lower and the 
incisions made not longer than 10 c. m. 
In 1901, the incisions were reopened on the upper as well as 
lower edge, and in 1002 only on the lower edge. 
The results of both years were as follows : — 
No. of Tree. 
1901. 
1 902. 
13 
T 4 
19 
20. 
! 
t 
1 ’ 
14 
19 
. 
20 
No. of rainy days, M. M. 
Height of tapping, M. 
Tapped surface M a- 
Total length of incisions c. m. 
Total yield, Grs. ... 
Yield per M a. of tapped surface Grs. 
IO 
3 - 28 
4 - 33 
5- 88 
968 
224 
4 
3-66 
443 
667 
630 
142 
5 
3 -o 
3-39 
356 
948 
280 
8 
3-67 
4-5 
405 
958 
213 
1 3 
0,65 
0.97 
20Q 
600 
619 
3 
0.62 
0.91 
160 
460 
506 
13 
i -5 
2.03 
320 
1500 
732 
13 
2.0 
320 
1230 
615 
Inasmuch as the temperature variations during both tapping 
periods were not the ime (by 13 and 14, he one in 1901 was more 
