two hundred and eighteen and one hundred and seventy feet respectively; but the deepest cut of all is at Tamborcito, about twenty-six miles from Greytown. Here the high ground north of the canal approaches so close to the river that a cut through it becomes imperative. The ridge is narrow, however, the width at the top being only a few feet and at the level of the water in the canal less than three thousand feet, but the extreme depth of the cut is two hundred and nineteen feet. The borings show that it is nearly all hard rock. The less heavy cuts will also be in firm ground, but the exact character of the material cannot be stated until the borings now in progress have been completed.

The most difficult engineering work in connection with the Nicaragua Canal project is the construction of a dam across the San Juan River to hold back the waters of the lake and enable its level to be regulated. It is of great importance

that this dam should be located above the mouth of the San Carlos River, as the latter discharges at times as much as 100,000 cubic feet of water per second, carrying with it great quantities of sand.

Lake Nicaragua, which forms a part of the summit level, is about one hundred miles long and forty-five miles wide, and is distant only about twelve to thirty miles from the Pacific. Originally it was an arm of the Pacific Ocean, but the shifting of the continental divide cut it off from the sea. The lake discharges through the San Juan River into the Caribbean Sea near Greytown. For the upper half of its course the San Juan winds through hilly country. Neither it nor any of its tributaries in this section carries much sediment, and a slack water navigation by means of locks and dams is practicable. But half way down its course the San Juan River receives the waters of the San Carlos which carry great quantities of

height of nearly 15,000 feet. Receiving the drainage of the slopes of the Himalayas and of a little-known Tibetan range running parallel with these mountains, it soon becomes a stream wide and deep enough to be navigable. There is a considerable boat traffic upon it, at an elevation but little below the summit of Mt. Blanc. It flows due east for some eight hundred miles, receiving numerous large tributaries from both south and north, and when near Lhasa it is, at low water, nearly a third of a mile wide and twenty feet deep; in flood, two miles wide and of unknown depth. In longitude 94° E. it makes a sharp bend to the south, and passes through the Himalayas in a course known only to the savages who dwell upon its precipitous banks.

When last seen by an explorer it is at a height of from eight to eleven thousand feet, but when it emerges in Assam it is only four hundred feet above sealevel. From this point it pursues its sluggish way for another eight hundred miles as the Brahmaputra to the Ganges and the Bay of Bengal. There has been a long controversy, into the details of which it is not necessary to enter, as to whether the Irawadi or the Brahmaputra is the continuation of the Tsangpo. Though there has been as yet no direct evidence the last expedient of throwing in marked logs in Tibet having failed the general consensus of scientific opinion is in favor of the Brahmaputra, and the latest English gazetteer describes it under this name.

It is hardly to be expected that pure science will be much benefited by the lifting of the veil which hangs over this. part of the river's course. But there can be little doubt that it hides scenes of magnificent beauty and grandeur which will thrill the expectant world, and give it new and nobler conceptions of the sublimity of nature.

The imagination fails to grasp the reality, as there is no other instance on earth of a large river dropping eight

thousand feet in one hundred and fifty miles, plunging with the mad rush of a mountain-brook hemmed in by ranges whose peaks are from thirteen to twentytwo thousand feet in height. The native testimony is conclusive as to the existence of at least one awe-inspiring fall before Tibetan territory is left. A scientific journal* published, a few years. ago, a copy of a picture of them by a native Tibetan artist who lived in their vicinity. It shows them enveloped in clouds of mist and spray, and the cliffs are covered by sub-tropical vegetation. The local lamas relate to the awestruck pilgrim that amid the thundering water stands a king-devil, placed there under a spell by the lamas, and, when the river is low, the faithful can see his figure looming dimly through the falling waters.

It has not been from the lack of the spirit of adventure, or because of the natural difficulties presented by the region-great though they doubtless are -that no white man has solved the mystery of this part of the river's course. Its attempted ascent from the plains of Assam has been absolutely prohibited. hitherto by the Indian Government on the entirely reasonable ground that there is almost a certainty that the explorer would be killed by the savage Mishmis, who are intolerably jealous of the presence of a stranger in their country. This would necessitate a punitive expedition costly in treasure and in life. -an evil by no means commensurate with the gain of having satisfied what is, after all, pure curiosity. The Tibetan officials also, while preventing so far as they are able any white men from entering Tibet, for some unknown reason forbid Tibetans even to attempt to descend the river beyond their own frontier.

The Tsangpo has been explored, however, with the exception of this one hundred and fifty miles, notwithstand

*Geographical Journal, vol. 5, p. 258.

ing the opposition of the Tibetans and the difficulties presented by the highest mountain region in the world, though not by white men. At any time within the last thirty-five years the trans-Himalayan traveller might have met a caravan of Tibetan and Indian traders with their pack-laden sheep climbing or descending some steep mountain-pass, or crossing the Tsangpo on rafts. Walking humbly with the servants and slaves, for to walk is a mark of servitude with those people, there would be an Indian with tea-bowl and prayer-barrel suspended at his girdle, counting his rosary as he walked, differing in nothing apparently from his companions except in his more intelligent face and the greater interest with which he noted everything about him. But open his prayer-barrel, which he piously twirls when he comes to some particularly dangerous spot, and there will be found in it, instead of the scroll with the Buddhist prayer, "Om mani padmi hom," notes of the journey after the boundary was crossed, observations with sextant and compass, and a simple route-survey showing the length of each day's march, the relative. position of the prominent peaks, the course of the streams, and their approximate breadth and depth. Examine closely his rosary, and one would discover to his surprise that, instead of the orthodox one hundred and eight beads, there were only a hundred, and that he dropped one at every hundred steps, which were uniformly two and a half feet long. If he were watched carefully he would be seen to steal from camp at night, when all else were sleeping, if biting wind, freezing cold, and driving snow permit, with his box and tea-bowl. Taking from beneath the false bottom of his box a few instruments, and pouring some quicksilver into his tea-bowl for an artificial horizon, he makes an observation of some star, notes the condition of barometer and thermometer, compares his chronometer with his watch, and then goes back to camp to write up his

journal, and at length to sleep. Years after, the traveller might see this same man at the Great Trigonometrical Survey in Calcutta reading to an English officer his journal, explaining his observations and route-survey, and narrating his adventures-in one instance these included a seven years' slavery in Tibet. He asks who he is, and is amazed to learn that he is only a school-master in a little Himalayan village in the district of Kumaon.

What is his reward for these year-long toils, sufferings, and dangers, this daily risking his life in an attempt to add to the world's knowledge? A little piece of land, possibly a small pension, and, while he is able to serve-oblivion. But soon the scientific journals will be full of accounts of the wonderful journey of the native Indian explorer, the great extent and marvellous accuracy of his survey, his pluck and endurance, his fertility of resource, and, above all, his singlehearted devotion to the cause of science. If his services are publicly recognized by some great Society, with the names of world-renowned explorers, we read merely, "The Pundit employed by Captain T. G. Montgomerie-a gold watchfor his route-survey in Great Tibet.” *

It was in 1861 that the successful opposition of the Tibetans to the exploration of the trans-Himalayan region, by Europeans, as well as the fact that Indian traders were permitted to travel freely throughout Tibet, suggested to an officer connected with the Great Trigonometrical Survey of India the expedient of employing native surveyors.

The village school-master, Nain Singh, who had been in the service of the brothers Schlagintweit during their explorations in Kashmir, was the first man to re

Royal Geographical Society Year-Book, 1899, p. 208. It should be said, however, that in 1877 the patron's medal was bestowed on the Pundit Nain Singh-then incapacitated for further service. Two others are also mentioned by name in the list of recipients of awards.

ceive the necessary training for the work. At the head-quarters of the Survey he was taught the use of the sextant, compass, etc., to recognize all the larger stars, to walk with paces of uniform length, and to make a simple route-survey.

When

these things had been sufficiently acquired, he was sent to explore the Tsangpo from its source to India, if possible. It was 1865 before he succeeded in establishing himself in Tibet as a trader desiring to buy horses and at the same time, as a pious Buddhist, to do homage to the Lhasa Lama. His "instrumental equipment consisted of a large sextant, two box sextants, prismatic and pocket compass, thermometers for observing temperature of air and of boiling water, pocket chronometer and common watch, with apparatus, the latter reduced as much as possible." After numerous adventures he finally reached Lhasa, where he had an interview with the Grand Lama, whom he described as a fair and handsome boy of about thirteen years of age, seated on a throne six feet high, attended by two of the highest priests, each holding a bundle. of peacock feathers. In this journey he was able to follow the course of the river only to the neighborhood of Lhasa, some six hundred miles. Nor did he succeed in tracing it farther in a second journey made seven years later-a journey memorable, however, from the fact that he

made a route survey of 1,319 miles, 1,200 of which were through country never previously explored, and took four hundred and ninety-seven observations. During all this time he was known to the scientific world only as the "pundit," but the sufferings of this last journey having so affected his health as to compel him to give up his connection with the Survey, his name was disclosed. He has been followed by others, among whom those known as A-k, D—m—g, and K. P. have accomplished the most in trans-Himalayan exploration, all men of like courage, endurance, and animated by a singleminded devotion to their duty. But none have succeeded, as yet, in tracing the Tsangpo's course through the mountains. to Assam.

But there are indications of a change of feeling of the rulers of Tibet toward the Indian Government which promises free intercourse between the two countries in the not distant future. As the deadly hostility of the Mishmis to strangers penetrating their mountain fastnesses has been largely due to Tibetan influence, we may look in time to a similar change among them to friendliness. If this should be the case, we trust that the man who lifts the veil which shrouds this wondrous passage of the river through the Himalayas may be one of that noble band, a native Indian surveyor.