Besides being familiar with the nature and use of poisons the Cham are also expert in concocting stupefying drugs and narcotics of all kinds. They often poison the air of a room in which a patient is lying by blowing stupefying vapours through hollow canes inserted in the wattled walls. The effect of these fumes is to make the victim sleep more heavily and the criminals take advantage of this circumstance to rob him at their leisure.
I had a vivid personal experience of this diabolical procedure. One evening I arrived with my escort at a house which our coolies had built specially for us and where we were to stay several weeks. The furniture consisted of nothing more than a bamboo bedstead supporting a mattress of cotton wadding. My room was very narrow and the seven cases which contained my instruments and cooking utensils were all the furniture I needed in addition. I told my boy to push two of these cases under the bed in order to save space. We had been marching all day under a tropical sun and I flung myself on the mattress and fell asleep at once. I awoke, according to habit, at about four in the morning and was surprised to feel myself so cramped that I could hardly move. To add to my astonishment I could not find my matches which I always kept within reach. The case which I had placed to serve as a bedside table had likewise disappeared.
With great effort I rose from bed and stumbling at each step managed to get out of the house. My sole garment was my pyjamas, for my clothes had followed the matches. It was still dark and I soon collided with an obstacle which proved on investigation to be one of the cases. I was somewhat alarmed and called for my servants. No one answered. A feeling of overpowering drowsiness overcame me and I had just time to get back to my bed before I fell asleep again. When morning came my orderly came in to announce that six out of the seven boxes were scattered about the outskirts of our camp. Locks had been forced and all my papers, instruments, photographic plates and prints, and wallets ruthlessly thrown out after obvious examination. It was plain that the burglars had been hunting for bank-notes. Fortunately I had no money in the cash-box. I had left the few thousand piastres which constituted our reserve with a colleague, so the total haul did not amount to more than two silver bangles and a few gewgaws, which together were not worth more than ten piastres.