After encircling the tree-trunk with these marks--about ten inches apart, the ring of them being over ten feet above the ground, the man stopped to explain their purpose. They were made merely to stimulate the flow of sap or latex. Each cut was a wound to the tree; it would rush a stream of sap to the spot to cleanse it, keep out insects and dust and to seal it until it could grow together again. That was nature’s way of protecting the tree when it was injured and while healing was in progress. If the tree were wounded in too many places at the same time it would be unable to cope with the situation and would die of the shock. But if the injuries were inflicted in gradually increasing numbers it would build up a strong defense by storing a large quantity of sap, ready to be rushed to any part of the trunk to clean new abrasions and protect them so soon as they were inflicted. Three or four days would be required to bring about this state of affairs in most cases, although in some trees it would take a week. That would be David’s first task--to make circles of incisions each morning to stimulate the trees to action. Next, he was told the rules that had to be observed in tapping the trees. The cuts must be ten inches apart and each new ring must be ten inches below the last one. Also, the position of each incision had to be halfway between those above, so that two days’ work would look like this V V V V V V V V Only one other thing remained to be told. No tree was to be disturbed unless it had a circumference of six spans half a meter above the ground. When, on the fourth or fifth day, the milk began to flow in quantity sufficient to be collected, a strip of tough palm midrib was tied around the trunk near the base. One side was pushed down a few inches; when the milk ran down the trunk it was stopped by the girdle and flowing along it soon reached the lowest part where a large leaf folded into a cone was suspended to receive it. It all looked very simple and David was sure he would have no trouble in following the instructions given him. On the return journey he snapped twigs continually so that he could easily find his way over the same route the next day. He was back on the trail early, starting at the same time as the others, who branched away in all directions. The long-handled ax was in his hands and the revolver, which he now always carried, was in its holster at his side. Most of the men had a firearm of some kind; others had bows and arrows, in the use of which they were proficient, having learned the art from the Indians. There was no trouble in picking up the trail of the previous day, and the bent twigs with the silvery under side of the leaves showing plainly, made it easy to follow the route that had been selected for him.