459 



The Experiments Reviewed 

 Notes. 



Experiment I. 



From August, 1905 to July, 1906 or a period of one year, three 

 tappings have been carried out, making a total number of 72 days 

 cr incisions resulting in 134 lbs. 2 oz. of dry rubber or an average, 

 of nearly 2 lbs. 1 1 oz. per tree. If to this is added 30 % for scrap 

 and clot (which may vary from 25 % to 40 %) the average per 

 tree is about 3^ lbs. The tappings irclude one evening period 

 and it may be noticed that the ratio of caoutchouc to latex for the 

 second period or evening tappings is better than the first or 

 morning tappings although the interval of rest was only 2\ months 

 or slightly less. This result stands alone and indicates the neces- 

 sity of experiments and observations over a long period. 



Experiment II. 



The interval of rest between the two periods of tappings was 

 under months, the second comparing unfavourably with the 

 first period and the evening poorer than, the morning. The result 

 is striking as the ratio of caoutchouc to latex in the second period 

 is very low partly due to evening tapping but as may be seen the 

 difference is more marked in respect of caoutchouc than latex, arc? 

 it would appear that had the time been reversed the best flow of 

 latex would have been obtained by daily tapping instead of alter- 

 nate days. The average yield per tree (with 30 % scrap, etc. 

 added) is 2 lbs. 3! ozs. for two pericds of tappings only, the second 

 or last tappings being most probably marre d by (a) insufficient 

 interval of rest, (b) commencement of the wintering cr dormant 

 season of the trees. 



Experiment III. 



Exactly an interval of two months' rest, which further emphasises 

 the necessity of a longer period and the advantage of morning ever 

 evening tapping. Considering that these are sn ail trees the first 

 tapping may be described as satisfactory, and the flew of latex at 

 the second tapping, fair, but the return of caoutchouc is remarkably 

 poor and the average per tree is reduced and only amounts to- 

 1 lb. 5 ozs. 



Experiment IV. 



The variations ef different groups is strikingly illustrated as 

 shewn in the details ef this experiment. The difference in yield 

 of latex between the two pericds is only £03 c zs. c/c and it is 

 probable that had all ihe groups in the secend } eric d of tappings 

 been full herring-bone incisions instead of single incisions the 

 margin wculd have been much less, still the single incisions com- 

 pare favourably with the full incisions, but the ratio of caoutchouc 

 is a considerable drop although an improvement cn previous figures 

 no doubt due to the longer icst — the interval being four months,, 

 and the average gross yield per tree is 2 lbs. 4 J czs. 



