Our English comrade, who had travelled all over South America, gave us this information as we rode along. He stated, that he had often considered it a great relief, a sort of escape from purgatory, while on his travels he parted from one of the yellow or white water streams, to enter one of the “rios negros.” Many Indian tribes settled upon the banks of the latter solely to get clear of the “plaga de mosquitos.” The Indians who reside in the mosquito districts habitually paint their bodies, and smear themselves with oil, as a protection against their bites; and it is a common thing among the natives, when speaking of any place, to inquire into the “character” of its mosquitoes!
On some tributaries of the Amazon the mosquitoes are really a life torment, and the wretched creatures who inhabit such places frequently bury their bodies in the sand in order to get sleep! Even the pigments with which they anoint themselves are pierced by the poisoned bills of their tormentors.
Besançon and the Kentuckian both denied that any species of ointment would serve as a protection against mosquitoes. The doctor joined them in their denial. They asserted that they had tried everything that could be thought of—camphor, ether, hartshorn, spirits of turpentine, etcetera.
Some of us were of a different opinion, and Ike settled the point soon after in favour of the dissentients by a practical illustration. The old trapper, as before stated, was a victim to the fiercest attacks, as was manifested by the slapping which he repeatedly administered to his cheeks, and an almost constant muttering of bitter imprecations. He knew a remedy he said in a “sartint weed,” if he could only “lay his claws upon it.” We noticed that from time to time as he rode along his eyes swept the ground in every direction. At length a joyous exclamation told that he had discovered the “weed.”
“Thur’s the darned thing at last,” muttered he, as he flung himself to the ground, and commenced gathering the stalks of a small herb that grew plentifully about. It was an annual, with leaves very much of the size and shape of young garden box-wood, but of a much brighter green. Of course we all knew well enough what it was, for there is not a village “common” in the Western United States that is not covered with it. It was the well-known “penny-royal” (Hedcoma pulegioides), not the English herb of that name, which is a species of mentha.
Redwood also leaped from his horse, and set to plucking the “weed.” He too, from experience, knew its virtues.
We all drew bridle, watching the guides. Both operated in a similar manner. Having collected a handful of the tenderest tops, they rubbed them violently between their palms—rough and good for such service—and then passed the latter over the exposed skin of their necks and laces. Ike took two small bunches of the stalks, crushed them under his heel, and then stuck them beneath his cap, so that the ends hung down over his cheeks. This being done, he and his comrade mounted their horses and rode on.
Some of us—the hunter-naturalist, the Englishman, and myself—dismounted and imitated Ike—of course under a volley of laughter and “pooh-poohs” from Besançon, the Kentuckian, and the doctor; but we had not ridden two hundred paces until the joke changed sides. From that moment not a mosquito approached us, while our three friends were bitten as badly as ever.
In the end they were convinced, and the torment of the mosquitoes proving stronger than the fear of our ridicule, all three sprang out of their saddles, and made a rush at the next bed of penny-royal that came in sight.
Whether it is the highly aromatic odour of the penny-royal that keeps off these insects, or whether the juice when touched by them burns the delicate nerves of their feet I am unable to say. Certain it is they will not alight upon the skin which has been plentifully anointed with it. I have tried the same experiment often since that time with a similar result, and in fact have never since travelled through a mosquito country without a provision of the “essence of penny-royal.” This is better than the herb itself, and can be obtained from any apothecary. A single drop or two spilled in the palm of the hand is sufficient to rub over all the parts exposed, and will often ensure sleep, where otherwise such a thing would be impossible. I have often lain with my face so smeared, and listened to the sharp hum of the mosquito as it approached, fancying that the next moment I should feel its tiny touch, as it settled down upon my cheek, or brow. As soon, however, as it came within the influence of the penny-royal I could hear it suddenly tack round and wing its way off again, until its disagreeable “music” was no longer heard.