These experiments favour nltftui ng over evening tappings,, al- 
though our evening work commence 1 as late in the day as possible, 
starting about 5 o'clock, and for this discrepancy, or rather the 
effect produced on the flow of lates, there is a very good reason 
which I fancy, has been overlooked. From a series of tests and 
measurements I conclude there can be no doubt that the flow of 
latex depends entirely on the pressure of water, and the contraction 
and expansion of a tree during the course of the day is considerable. 
A tree of 3 feet girth at 3 feet from the ^ground, measuring exact!}’ 
3 feet at 6 A. M,. would by afternoon, according to the brightness of 
the day, contract to a maximum of l inch, and by 6 r.vr. or soon 
afterwards expand to early morning measurement. Or, if a ligature 
be fixed tightly on a tree it can be observed that in the early morn- 
ing the ligature is fully stretched, and by afternoon, if a bright 
warm day, is quite slack, or partly so, according to the day, and as 
the evening advances gradually braces up. On wet days the liga- 
ture is expanded, to tension point and the flow of latex is consider- 
ably increased, but contains a high percentage of water as is seen by 
the excessive residuum when the latex has coagulated. I11 wet 
weather it seems-best to tap some hours after a storm, and to get 
the best result from evening tappings the work should be deferred 
as late in the day as possible. 
Doubtless there is one method of tapping Para trefcs better than 
others, and the work that is being carried on in so many parts of 
the world should soon decide which is the one best suited for 
extracting the maximum yield of latex at the minimum risk of 
injury to the tree, but for a substantial increase in the yield of 
latex, I infer that improvement I i e -- in the direction of a thorough 
knowledge of the requirements of the tree, and it may be necessary 
for planters to expand their ideas in respect of the distance apart 
trees' should permanently stand, and to obtain a well developed 
tree which shows a satisfactory annual increment of growth, 30 
feet apart is but a moderate and rational distance. 
It will be seen that in a few instances, tappings have been con- 
tinued for 18 times, and it will be noted that in nearly every instance 
the decrease below maximum yield amounted to very little. Ii ap- 
pears that on big trees the scar does not increase at the same ratio as 
on small ones, and had a gross yield been attempted, several more 
tappings woirld have been obtained, and as might be expected the 
2nd, 3rd and perhaps 4th tappings omitted, so that the 1 8th tapping 
would then have stood as the 15th. Of course there is a limit as to 
how wide a scar should be, but I have never seen a tree injured by 
removing an extravagant amount of bark, it is in the depth of the 
incision that risk of injury lies. 
As to implements tor tapping, we have used an ordinary pruning 
knife and a smalt I inch carpenter's chisel, which have answered 
the purpose very well. At the present time there are many imple- 
ments for tapping and so long as it gives a clean cut the one that 
expedites the operation. of tapping most should be the best. 1 he 
r I inch carpenter's chisel for single incisions is not an implement 
