Popular Science Monthly/Volume 17/July 1880/A Zoological Enigma
|A ZOÖOGICAL ENIGMA.|
PROFESSOR ULRICI, the modern Rosicrucian, defends spiritualism on the plea that it meets the demands of what he calls our Wunderbedürfniss, the propensity to indulge in wonderment, which he includes among the normal instincts of the human mind. A taste for enigmas is a primitive manifestation of the thirst for knowledge in general, and thus akin to the very primum mobile of all intellectual progress, but in its legitimate forms that propensity might exert its functions on an ample field within the domain of the strictly physical sciences. The problems of modern chemistry, physiology, and natural history confront us with countless unsolved questions, with phenomena more wonderful in their reality than any dreams of hysterical hallucinations or of the wildest fancy. The marvel-hunter who gropes his way through the arcana of an unknown world might pursue his quarry more profitably on the hunting-grounds of his own planet—more successfully, too, if he would keep his eyes open. The sunlit fields and the gaslit laboratory reveal truer wonders than the dark closet of the spook-manufacturer; the tests of the naturalist yield the same result at all times and under all circumstances—their success does not depend on the obfuscation of the locality (and of the witnesses); it is not jeopardized by the presence of skeptical critics, or the absence of discreet accomplices. Many notorious phenomena, apparently familiarized by their frequency, in reality still involve mysteries whose solution might disclose new paths of research, or reflect a helpful light upon the problems of a kindred science. The diffusion of contagious diseases, submarine currents, the synchronism of storms and shooting-stars, hibernation, the survival of reptiles in close-grained rocks, the weather-wisdom of the tree-toad and trap-door spider, for instance, have been only partially explained; nay, every amateur naturalist may indulge in an experiment whose general result seems so utterly inexplicable on any recognized scientific principle that it reduces our speculations to a phraseology of metaphors—to the nomenclature of an unknown quantity.
We often hear of the wondrous sagacity—generally ascribed to memory or acuteness of scent—which enables a dog to find his way home by unknown roads, even from a considerable distance. I think it can be practically demonstrated that this faculty has nothing to do with memory, and very little with scent, except in a quite novel sense of the word.
Last fall, my neighbor, Dr. L. G——, of Cincinnati, Ohio, exchanged some suburban property for a house and office near the City Hospital, and at the same time discharged a number of his four-footed retainers. A litter of poodle puppies were banished to Covington, Kentucky, across the river, and two English pointers were adopted by a venatorial ruralist in the eastern part of Ohio. The puppies submitted to exile, but one of the pointers, like the black friar in the halls of Amundeville, declined to be driven away. He returned, by ways and means known to himself alone, once from Portsmouth and twice from Lucasville in Scioto County, the last time in a blinding snow-storm and under circumstances which led his owner to believe that he must have steered by memory rather than by scent. But how had he managed it the first time? The matter was discussed at a reunion of sportsmen and amateur naturalists, and one opponent of the doctor's theory proposed as a crucial test that the dog be chloroformed, and sent by a night-train to a certain farm near Somerset, Kentucky (one hundred and sixty miles from Cincinnati): if he found his way back, he could not have done it by memory.
The doctor objected to chloroform, remembering that dogs and cats often forget to awake from anæsthetic slumbers; but finally Hector was drugged with a dose of Becker's elixir (an alcoholic solution of morphine), and sent to Somerset in charge of a freight-train conductor. The conductor reports that his passenger groaned in his stupor "like a Christian in a whisky-fit"; at length relieved himself by retching, and went to sleep again. But in the twilight of the next morning, while the train was taking in wood at King's Mountain, eighteen miles north of Somerset, the dog escaped from the caboose and staggered toward the depot in a dazed sort of way. Two brakemen started in pursuit, but, seeing them come, the dog gathered himself up, bolted across a pasture, and disappeared in the morning mist. At 10 a. m. on the following day he turned up in Cincinnati, having run a distance of one hundred and forty-two miles in about twenty-eight hours.
Still the test was not decisive. The dog might have recovered from his lethargy in time to ascertain the general direction of his journey, and returned to the northern terminus by simply following the railroad-track backward. The projector of the experiment, therefore, proposed a new test with different amendments, to be tried on his next hunting-trip to central Kentucky. On the last day of January the dog was sent across the river, and, nem. con., the experimenter fuddled him with ether, and put him in a wicker basket, after bandaging his nose with a rag that had been scented with a musky perfume. Starting with an evening train of the Cincinnati Southern Railroad, he took his patient southwest to Danville Junction, thence east to Crab Orchard, and finally northeast to a hunting rendezvous near Berea in Madison County. Here the much-traveled quadruped was treated to a handsome supper, but had to pass the night in a dark tool-shed. The next morning they lugged him out to a clearing behind the farm, and slipped his leash on top of a grassy knob, at some distance from the next larger wood. The dog cringed and fawned at the feet of his traveling companion, as if to conciliate his consent to the meditated enterprise, and then slunk off into a ravine, scrambled up the opposite bank and scampered away at a trot first, and by and by at a gallop—not toward Crab Orchard, i. e., southeast, but due north, toward Morgan's Ridge and Boonsboro—in a bee-line to Cincinnati, Ohio. They saw him cross a stubble-field, not a bit like an animal that has lost its way and has to turn left and right to look for landmarks, but, "like a horse on a tramway," straight ahead, with his nose well up, as if he were following an air-line toward a visible goal. He made a short détour to the left, to avoid a lateral ravine, but farther up he resumed his original course, leaped a rail-fence, and went headlong into a coppice of cedar-bushes, where they finally lost sight of him.
A report to the above effect, duly countersigned by the Berea witnesses, reached the dog's owner on February 4th, and on the afternoon of the following day Hector met his master on the street, wet and full of burrs and remorse, evidently ashamed of his tardiness. That settled the memory question. Till they reached Crab Orchard the dog had been under the full influence of ether, and the last thing he could possibly know from memory was a misleading fact, viz., that they had brought him from a southwesterly direction. Between Berea and Cincinnati he had to cross two broad rivers and three steep mountain-ranges, and had to pass by or through five good-sized towns, the centers of a network of bewildering roads and by-roads. He had never been in that part of Kentucky before, nor ever within sixty miles of Berea. The inclination of the watershed might have guided him to the Kentucky River, and by and by back to the Ohio, but far below Cincinnati and by an exhaustingly circuitous route. The weather, after a few days of warm rains, had turned clear and cool, so that no thermal data could have suggested the fact that he was two degrees south of his home. The wind, on that morning, varied from west to northwest; and, if it wafted a taint of city atmosphere across the Kentucky River Mountains, it must have been from the direction of Frankfort or Louisville. So, what induced the dog to start due north?
"Instinct." Of course, but the demands of science are not to be satisfied with conventional phrases. Blind instincts we may call such feelings as hunger, the craving after fresh air, and other promptings of our internal organs; also, perhaps, the faculty of executing such uniform mechanical functions as the construction of an hexagonal cell or of a spheroid cocoon; but, if such faculties have to adapt themselves to variable and uncertain circumstances, they require the aid of a sense—i. e., of a discriminative organ. So the question comes back upon us, What sense aided the dog in the choice of his direction? Scent? It seems too impossible, though the assumption of a "sixth sense" would be the only alternative. A blind man finds his way through the mazes of a city, or an intricate system of halls and corridors, by what we might call locomotive memory—i. e., the faculty to remember a long series of turns in their due sequence and with the correct intervals of time or space. The sense of touch becomes here vicarious to eyesight. In the same way a wide-awake animal might take cognizance of certain locomotive data without the assistance of its eyes. It might feel the turnings of its rolling cage, and remember enough to imply the general direction. A stupefied animal could not do it. The olfactory power of a dog exceeds ours about as much as human eyesight exceeds that of a shrew-mouse. A dog will "set" a covey of partridges across a broad field, and can scent a tramp from a distance of half a mile. A nose that can track the faint scent of a rabbit through thickets of aromatic herbage might easily distinguish the atmosphere of a reeking manufacturing town at a distance of ten miles. At fifty miles it might be barely possible under the most favorable conditions of wind and weather; at one hundred and fifty miles it seems impossible under all circumstances. Besides, a dog would find his way to a backwoods cabin as readily as to a smoky metropolis. The question still recurs: How does he manage it? Should dogs be gifted with the faculty of determining geographical latitude and longitude by means of their noses?
The memory-hypothesis being disposed of, the scent-theory might be definitely settled by a simple operation, viz., destruction of the olfactory nerve. Any anatomist could do it. Helmholtz and Von Graefe made similar experiments with the optic nerve, even without inflicting permanent damage. A dog might be rendered scentless for a day or two, and a trip to the next county under the above-described collateral precautions would decide the point. Deerhounds, pointers, and terriers would be the best subjects. for the experiment; greyhounds are not only inferior in acuteness of scent but in sagacity in general; and collies and poodles, though marvelously clever in their peculiar spheres, seem to be almost destitute of what the French call the sens d'orientation (the sense of orientation—the process of determining the points of the compass).
Leaving the exegetical question out of view, I will here venture a conjecture in regard to the origin, or rather the original purpose, of the strange faculty. The common ancestor of all domestic dogs was probably some near relative of the Canis lupus, either the dog-wolf of the Hindoo-Koosh, or the Canis aureus, the Indian or African jackal. The puppies of all these canines are born in litters—from six to ten at a time, are helpless for the first ten weeks, and entail a great amount of trouble on their food-purveyors. The mother, perhaps straitened in her own means of support, has now to meet the demands of a greatly enlarged household, and in all probability the available supplies of animal food in her next neighborhood will soon be exhausted. Her forage excursions must be extended to greater and greater distances, in a barren country like northern Africa or Turkistan perhaps to remote oases and mountain-regions, hundreds of miles away. She-wolves that must have come from Lithuania or eastern Poland have been shot in northern Germany. Under such circumstances topographical instinct becomes a matter of vital importance, and where there is a want Nature always finds the means of supplying it. All our senses are comparatively rudimental. Every organ holds the possibility of an infinite functional development. In man the ability of distinguishing black from white has been perfected into the art of reading, the faculty of identifying at a single glance half a hundred multiform black marks on a white background. By constant practice and hereditary transmission of cumulative acquirements, the ability of remembering the bifurcation of a ravine, or of smelling a muskrat across a creek, was thus, perhaps, developed into the art of recollecting the ramifications of a vast mountain system or of scenting the atmosphere of a given locality athwart a continent.
Similar causes have produced similar results in other species of animals, for the sense of orientation is not confined to the genus Canis. Horses and goats show traces of the same talent; pigeons, crows, falcons, and all migratory birds possess it in a transcendent degree; also all migratory fishes and reptiles, shad, sturgeons, tunny fish, and marine tortoises. Now, there is no doubt that in most birds the olfactory sense is very feebly developed. Eagles, falcons, and sparrow hawks hunt by sight, and even condors and other vultures have been decoyed with sham carcasses, hides stuffed with straw or stones. Pigeons and chickens are very sharp-sighted and awaken at the slightest sound, but a noiseless thief can surprise them in any dark night—the sense of smell does not warn them. Von Haller went so far as to assert that birds can not smell at all, and that their nostrils are only respiratory apertures.
How, then, could carrier-pigeons find their way from Cleveland to Philadelphia? Belgian pigeons have carried letters from Paris to Namur and from Geneva to Brussels, in fourteen and twenty-two hours; and a gerfalcon, which Henri Quatre presented to the commander of a Mediterranean brigantine, returned from Tangier to Paris in a single day. Did they steer by sight? However telescopic their vision might be, the incurvation of the globe would preclude the idea.
The bird-of-passage instinct is much less wonderful. Cranes and geese might steer due south by the aid of the noontide sun, and return by inverting the process till they come in sight of familiar scenery. A Northampton swallow, flying at the rate of two miles a minute, could well afford to roam at random over the State of Massachusetts till she came in sight of the Holyoke range and Mount Tom. A sturgeon, too, might find his spawning-grounds at the mouth of the Ottawa by following the St. Lawrence upward till he reached the Chaudière of St. Anne. In short, the art of retracing a self-chosen route appears much less enigmatical. But even reptiles have crossed unknown seas by the aid of the same geographical second-sight which guided the Philadelphia pigeons to their native roost. According to a well-authenticated report, the crew of a British East Indiaman caught an enormous tortoise near St. Helena, marked it with the brand of the company, and quartered it in the cockpit, but in the English Channel their captive crawled on deck and plunged overboard. Two years after, the same tortoise was caught in Sandy Bay near Jamestown, on the south coast of St. Helena. No ocean-current could have carried it there; it must have navigated by its inner compass a distance of seven thousand English miles.
Should the occult sense be merely an unknown function of a well known organ? A person whose eyesight is limited to the range of his ear-shot would fail to comprehend how an earthly being could see stars beyond the boundaries of the solar system, and a nation of mole eyed men would speak of the instinct that enables a homo of a different species to reach a distant village by keeping his eye on the steeple. We may have a dormant rudiment of that same sixth sense. Perhaps it awakens in the pulmonary beatitude that expands our chests in the atmosphere of a sunlit forest, or in the nausea induced by the effluvium of a stagnant bayou. Neither sensation is necessarily dependent on the olfactory sense.
We have lost several faculties from sheer disuse, but it is not probable that their number includes the instinct of orientation. It is deficient in many of our fellow creatures, both of the higher and lower orders. Monkeys, sheep, black cattle, gallinaceous birds, lizards, and lepidopterous insects seem to be almost devoid of it. Should we not be able to detect some characteristic structural difference between monkeys, chickens, and lizards on the one hand, and dogs, pigeons, and tortoises on the other? A peculiar instinct must correspond to some peculiar organization, and I think that specialty could be determined in the domestic dog if anywhere. For many reasons the modus operandi of a function can be more easily observed in a docile mammal than in a reptile or a shy bird, and, if we hope to force the intrenchments of the enigma, we had better "fight it out on this line." If one of the five senses should be the functional medium of the strange instinct, there must be ways and means to identify it; if there is such a thing as a sixth sense, we should be able to locate its organ. The "intuitive cerebration" theory is untenable. In the well-known axiom that nothing comes within the ken of our intellect but what has entered by the gate of the senses, we may confidently substitute "intuition" for "intellect." In other words, we have few reasons to doubt and many reasons to suspect that every psychic emotion, as well as perception, is the reflex of some organic impression.