GEYSERS (Icelandic, geysa, to burst forth violently), intermittent hot springs found in various parts of the world. In Iceland the principal geysers are in the S. W. part of the island, about 35 m. N. W. of Hecla, and 70 m. from Reykiavik, the chief town. In a circuit of about two miles are more than 100 springs which send forth hot water, 50 or more in the space of a few acres. These are on the lower slope of a small hill of trappean rock, and above them in the steeper part of the hill under the cliffs of this rock are banks formed by the incrustations of ancient and now nearly extinct geysers. The springs are of different dimensions, and exhibit various degrees of activity; some are uniformly full and quiet, others are constantly boiling, and others only at intervals, with explosive discharges of water and steam. The vapors rising from them form clouds that are seen miles away. They are attended with sulphurous odors; and the geysers of other localities on the island deposit sulphur derived from the decomposition of the iron pyrites in the clays through which the hot waters penetrate. The chief spouting springs of the group are the Great geyser and the Great and Little Strokr. The Great geyser when quiet presents the appearance of a circular mound of silicious incrustations, enclosing a pool, with sides sloping inward at an average angle of 13°, and outward at a mean inclination of 8°. The height of the mound is about 20 ft. on the lower side, but only half as much on the upper side. The diameter of the basin varies from 50 to 60 ft., and its average depth is 4 ft. In its centre is the mouth of the vertical tube which connects it with the subterranean passages. This tube is about 9 ft. in diameter at its mouth, and 70 ft. in depth. When the geyser is inactive, the basin is filled to the edge with clear water, which has a mean temperature of 185° F. and runs gently down the mound, emitting clouds of steam; but for several hours after an eruption the tube is empty to the depth of 4 or 5 ft. At intervals of about an hour and a half a rumbling noise is heard, and the water heaves up in the centre, throwing an increased quantity over the margin. The great eruptions take place at irregular intervals, sometimes exceeding 30 hours. At these times loud explosions are heard beneath the surface, the water is thrown into violent agitation, it boils furiously, and at last is suddenly sent forth in a succession of jets, which increase in force till they become an immense fountain that is lost to view in the clouds of steam in which it is enveloped. The heights reached by these jets have been variously estimated by different travellers. The lowest estimate is 60 or 70 ft.; that of Von Troil in 1772 is 92 ft.; of Sir John Stanley in 1789, 96 ft.; of Lieut. Ohlsen, a Danish officer, in 1804, determined by a quadrant, 212 ft.; of Sir George Mackenzie in 1810, 90 ft.; and of Henderson in 1815, 150 ft. Later visitors, Lord Dufferin, Mme. Ida Pfeiffer, J. Ross Browne, and others, estimate the height at from 60 to 70 ft. The eruptions appear to be diminishing in force and frequency, and it is not improbable that they will cease altogether before the lapse of another century. The discharge continues only about five minutes, when the geyser subsides to a state of tranquillity. The Great Strokr, so named either from the Icelandic word meaning churn, or from stroka, to agitate, is only 300 or 400 ft. from the Great geyser, from which it differs in appearance in being an irregularly formed well, incrusted with silicious deposits, but having no basin at its mouth. Its orifice is about 8 ft. in diameter, diminishing to about 10 in. at the depth of 27 ft.; the whole depth is a little over 44 ft. The water for the greater part of the time is 10 or 12 ft. below the surface, and is continually boiling and seething, but at intervals of about half a day it breaks forth in a great eruption, throwing its water generally from 40 to 60 ft.; but Bunsen, who saw it in 1846, estimates it to be 151 ft. high. By throwing turf or stones into the well of the Strokr, an eruption can be brought on in a few minutes. The Little Strokr exhibits the same phenomena on a smaller scale. In the same vicinity are two large and quiet wells remarkable for their beautifully blue water. These were once active, and one of them is described by an English traveller as the Roaring geyser. It became tranquil immediately after an earthquake in 1789, when the Great Strokr first broke forth. The deposits of silica which accumulate around the geysers are derived from the small amount of this material which is taken up in solution by the hot water. By the analysis of Dr. Black, made upon 10,000 grains (about 5⅓ gills), it would appear that the whole amount of solid matter remaining dissolved in the cold water is only a little more than 1⁄1000 of the whole, the quantity examined yielding as follows: soda, 0.95; alumina, 0.48; silica, 5.40; muriate of soda, 2.46; dry sulphate of soda, 1.46; in all, 10.75. An analysis of the geyserite, or solid deposit, made by Forchhammer, gave the following result: silica, 84.43; water, 7.88; alumina, 3.07; iron, 1.91; lime, 0.70; soda and potassa, 0.92; magnesia, 1.06; total, 99.97. As the water evaporates and is chilled, the excess of silica is added to the surface around, filling the interstices of the mosses and grass, and making of these silicious petrifactions, while the living plants still thrive and shoot above the strong substance that binds together their roots and stems. Where the waters are found at a temperature of 98° C. (208.4° F.), M. Descloiseaux observed that the confervæ still flourished. The true theory of the cause of geyser eruptions is due to Bunsen. When in Iceland in 1846, he proved by a series of careful experiments that the temperature of the water in the geyser tube varies at different depths, as also at different periods between two eruptions, the changes always taking place in the same manner and with considerable regularity. Immediately before the eruptions there is a maximum temperature at the bottom of the well estimated at 260.6° F., and a minimum immediately after of 253.4°. The temperature of boiling water at the depth reached by the thermometer should be about 276° F. The water therefore in no part of the tube is hot enough to generate steam under the conditions. But the higher you ascend in the tube, the lower is the temperature at which water will boil. If then the column be thrown up by the generation of steam in the underground channels, the water at the bottom, which is near the boiling point, is brought to a height where it is sufficiently relieved from pressure to be converted into steam. The water in the tube is lifted still higher, until the steam condenses by contact with the cooler water, to which it imparts its latent heat. Each condensation makes a detonation, the subterranean explosion which precedes an eruption. By successive efforts enough of the superincumbent column is thrown off to raise nearly all the water in the tube to the boiling point, until at last the relief from pressure is sufficient to permit the ejection of the contents of the tube. This ejection continues until all the reservoirs around the geyser are emptied, when it subsides until the proper conditions are established again. A boiling spring becomes in time a geyser if, in building up around itself a mound of precipitated mineral, it forms a vertical tube of sufficient height and regularity to give a certain pressure of confined water; and when the tube reaches such an altitude that the water below cannot, in consequence of the increased pressure, reach the boiling point, the eruptions cease and the geyser becomes a mere cistern. It is a singular fact in the history of Iceland that no mention is made of the geysers until they are spoken of by Svenson, bishop of Skalholt, in the 17th century; and this is the more remarkable, as Ari Frode, who wrote of the geography and history of the island in the 11th century, spent his youth in their immediate vicinity. They bear unmistakable evidences of having been in operation in this district, if not in the exact places where they are now found, from remote periods.—The geysers of New Zealand are in the island of New Ulster, the most northerly of the group. About the centre of the island, near the ever active volcano of Tongariro, thermal springs, mud fountains, and geysers rise in more than 1,000 places, exhibiting phenomena more remarkable than those in Iceland. A portion of Lake Taupo boils and smokes as if heated by subterranean fires, and the average temperature of its water is about 100° F. North of it, a valley through which the Waikato river flows contains a great number of geysers, 76 having been counted in one group. These jets of water are of various height, and play alternately. About half way between the lake of Taupo and Plenty bay, on the coast, is the little lake of Rotomahana, covering 120 acres, whose temperature, raised by the hot springs which feed it, is about 78° F. This lake is surrounded by springs and fissures, from which steam, sulphurous gases, water, and mud are continually escaping. The most remarkable of these, the Tetarata (tattooed rock), is at the N. E. end of the lake, about 80 ft. above its level. It is described by Von Hochstetter as a crater-like excavation, with steep reddish sides, 30 to 40 ft. high, which are open toward the lake only. The basin of the spring is about 80 ft. long and 60 wide, and is filled to the brim with clear transparent water, which against the white incrusted sides appears of a beautiful blue color. Immense clouds of steam continually rise from it, obstructing the view of the surface, and the noise of boiling is always audible. At the margin the temperature is 183° F., but in the centre, where the water is continually in a state of ebullition to the height of several feet, it probably reaches the boiling point. The deposit, like that of the Iceland springs, is silicious, and the incrustations made by the overflow have formed on the slope a system of terraces, from 2 to 6 ft. in height, as white and almost as regular as if cut from marble, on each of which are circular basins, resplendent with blue water. These terraces, which cover an area of about three acres, have the appearance of a cataract plunging over natural shelves, which as it falls is suddenly turned into stone. Each stage has a small raised margin, from which slender stalactites hang down on the next below. At ordinary times but very little water ripples over these terraces, and only the principal discharge on the side forms a hot steaming fall; but sometimes, say the natives, the whole body of water is thrown up in an enormous column, emptying the pool. On the highest stage is an extensive platform, with a number of basins, from 5 to 6 ft. deep, the water showing a temperature of from 90° to 110° F. In the middle of this platform rises, close to the brink of the main basin, a rock island, about 12 ft. high, covered with mosses and ferns. From it a full view may be had of the interior of the boiling caldron, without danger. The rocks from which these springs derive their silica are rhyolites and rhyolithic tufas, which contain over 70 per cent. of it. An analysis of the solidified incrustation of the Tetarata, made by Mayer, gave the following result: silica, 84.78; water and organic substances, 12.86; sesquioxide of iron and alumina, 1.27; lime, magnesia, and alkalies, 1.09; total, 100.—In the United States, volcanic boiling springs exist in numerous localities west of the Rocky mountains. In the Colorado desert, between lat. 33° and 34°, and lon. 115° and 116°, are remarkable mud volcanoes and boiling springs. The desert at this point is below the level of the sea. The springs cover a space not more than a quarter of a mile square. This area is covered with soft mud, through which water and steam are constantly escaping, with a noise audible at a distance of ten miles. In some places the vapor rises steadily, with a sharp hissing sound; in others it bursts forth with a loud explosion, throwing water and mud to the height of 100 ft. Some of the boiling springs throw up a column of water 20 or 30 ft.; some have cones formed around them, and some have basins 100 ft. in diameter, in which the blue paste-like mud is ever bubbling and hissing. Many are incrusted with carbonate of lime, others with deposits of sulphur. The steam which rises from them is strongly impregnated with sulphur. Similar springs exist in New Mexico and in some of the other territories.—The so-called geysers of California are in Sonoma county, in a lateral gorge of the valley of Napa, called the “Devil's Cañon,” near the Pluton river. The narrow ravine, which is always filled with vapor, is shut in by steep hills, the sides of which, marked with evidences of volcanic action, are smoking with heat and bare of vegetation. A multitude of springs gush out at the base of the rocks. Hot and cold springs, boiling springs, and quiet springs lie within a few feet of each other. They differ also in color, smell, and taste. Some are clear and transparent, others white, yellow, or red with ochre, and still others are of an inky blackness. Some are sulphurous and fetid in odor, and some are charged with alum and salt. The “Steampipe” is an orifice in the hillside, about 8 in. in diameter, from which a volume of steam rises with a continuous roar to a height varying from 50 to 200 ft. In a cavity called the “Witches' Caldron” a mass of black fetid mud is ever bubbling with heat, the vapor from it depositing black flowers of sulphur on the rocks around. The surface of the ground about the springs, which is too hot to walk upon with thin shoes, is covered with the minerals deposited by the waters, among which are sulphur, sulphate of magnesia, sulphate of aluminum, and various salts of iron. These springs, none of which are properly geysers, are about 1,700 ft. above the sea.—The geysers at the head waters of the Yellowstone and Missouri rivers are probably the most wonderful on the globe, even those in Iceland and New Zealand sinking into insignificance when compared with them. The country lying between lat. 43° and 47° N., and lon. 110° and 114° W., comprising portions of the territories of Idaho, Wyoming, and Montana, is dotted with groups of hot springs, the remains of most remarkable volcanic manifestations, which began probably in the tertiary period. Earthquake shocks are still common throughout this region, and at some seasons of the year are very severe. The most of these springs are not geysers, but simply boiling mineral springs and mud volcanoes. The geysers proper are in the N. W. corner of Wyoming territory, on the Fire-Hole river, the middle fork of the Madison, which is one of the three principal sources of the Missouri. The basin in which they are situated was visited first by a party under Cook and Folsom in 1869. In 1870 Gen. Washburne, surveyor general of Montana, explored it with a party, among whom were Lieut. G. O. Doane and N. P. Langford; and in 1871 it was surveyed by Dr. F. V. Hayden, United States geologist, and by Col. J. W. Barlow and Capt. D. P. Heap, of the United States engineer corps. Dr. R. W. Raymond, United States commissioner of mining statistics, also visited and described the region in the same year. The geysers lie in two large groups, in what are called the upper and lower geyser basins. The lower basin, beginning near the junction of the East and Middle forks of the Madison, comprises an area of about 30 sq. m. The springs are divisible into three classes : 1, those which are constantly boiling; 2, those which are agitated only at particular periods; 3, those which are always tranquil. In the geysers proper the water is usually quiet until a short time before an eruption. Dr. Peale, who examined them in 1871, in connection with Prof. Hayden, divides the springs into seven principal groups. In the first group, at the N. end of the basin, the temperature of 67 springs, occupying a space of about a quarter of a mile wide by two miles long, was recorded. The lowest was 106° F., the highest 198°. The temperature of the air was 50°. Some of these are geysers, projecting the water from 2 to 5 ft., but most of them are simply silicious springs, a few being chalybeate. The second group, which lies 2½ m. further S., nearer the centre of the basin, occupies an area of about three fourths of a mile. Sixteen springs here ranged in temperature from 140° to 196°. The temperature of the air was from 55° to 66°. This group is composed principally of geysers, many of them throwing water from 5 to 10 ft. high. The principal one, on the slope of a hill, is about 20 ft. in diameter, with a rim 5 ft. wide and 5 ft. high. The column of water thrown from it is very wide, and reaches the height of 50 ft.
The Thud Geyser.
Another is named the Thud geyser, from the dull suppressed sound given off as the water rises and recedes. It has a beautiful scalloped rim, with small basins around it. This group of geysers is said to resemble a factory village, the steam rising in jets from more than 100 orifices. The third group lies three fourths of a mile S. E. of the second, at the base of a spur of the mountains, and extending up a ravine about 1,000 yards. They cover a space 500 yards in width. The temperature of 20 springs ranged from 130° to 196°. Near the centre of the group is a small lake, 600 ft. long by 150 wide, on the E. shore of which is a geyser spouting to the height of from 15 to 20 ft. There are three sulphur springs here, the only ones in the region, and S. E. of the lake is an iron spring. About 1,000 yards further S. is the fourth group, in a ravine about 1½ m. long and 300 yards wide. It contains many springs and geysers, the temperature of 42 of which ranged from 112° to 198°, the temperature of the air being about 60°. The principal geyser is at the mouth of the ravine. Its basin is circular and about 60 ft. in diameter, and its spring, in the centre, from 15 to 20 ft. The water is blue, and is constantly agitated. When in eruption the column is projected 100 ft. high, and is accompanied by immense clouds of steam. Near the upper end of the ravine is a spring around which the deposit is black, instead of the usual white. The fifth group, on the banks of the Fire-Hole river, is the largest of all, covering nearly a square mile and comprising a great number of springs and geysers. The temperature of 95 examined ranged from 112° to 196°, the air at the time being 70°. None of them are of much importance. One, from its resemblance to a shell, is named the Conch spring; its basin is triangular, from 8 to 10 ft. in diameter. A little below it, on the bank of the river, there is a fine geyser, with a crater 3 ft. high. The Horn geyser has a crater like a horn, about a foot in diameter at the top and 6 ft. at the base; it is in constant ebullition. The Bath spring has a square basin 30 ft. across, of unknown depth. The Cavern has a basin 15 by 20 ft. wide and 20 ft. in depth; the water is of a bright blue tint, and of wonderful clearness. The mud springs of this group are from an inch or two to 20 or 30 ft. in diameter, their contents varying from turbid water to stiff mud. They are in a constant state of agitation. The mud is of different colors, being pure white in some, in others brown, black, or blue. The sixth group is 2 m. S. W., on a small stream flowing into the Fire-Hole. They are in an open, prairie-like valley, for the most part marshy. The temperature of 34 of the springs varied from 106° to 198°. One of them is strongly chalybeate. The seventh group is on the Fire-Hole river, about 2½ m. S. of the preceding. The temperature of 20 of the springs ranged from 132° to 196°, when the air was from 70° to 76°. The largest has a basin over 400 ft. in diameter. Below it is another huge spring, named the Caldron, the view of which is almost obscured by the dense clouds of steam rising from it. The upper geyser basin lies in the valley of the same river, about 8 m. S. of the lower basin. It is not so large as the latter, covering an area of only about 3 sq. m., and it contains fewer springs; but the phenomena exhibited are far more remarkable. Most of the springs and geysers are near the river, extending along on both banks about 3 m. The temperature of 106 of them ranged from 113° to 196°, the average being over 170°, the temperature of the air being 67°. At the head of the valley, at its southern extremity, stands Old Faithful, a geyser so called for its regularity; it spouts at intervals of about an hour, throwing a column of water 6 ft. in diameter to a maximum height of 130 ft., and holding it up by a succession of impulses from 4 to 6 minutes. The great mass of the water falls directly back into the basin, flowing over the edges and down the sides in streams. When the action ceases, the water recedes out of sight, and nothing but the occasional hiss of steam is heard until the time approaches for another eruption. Its crater is a conical mound of geyserite about 12 ft. high, measuring at the base 145 by 215 ft. and at the top 54 by 20 ft. Near it are four extinct geyser cones. On the opposite side of the river are the Beehive and the Giantess. The former is a silicious cone 3 ft. in height, 20 ft. in circumference at the base, and 3 by 4 ft. in diameter at the top, with an oval orifice 3 by 2 ft. in diameter. When in action, which occurs once in about 24 hours, it throws a column of water entirely filling the crater to a height which, says Langford, was found by triangular measurement to be 219 ft. The eruption lasted 18 minutes, and the stream did not deflect more than 4° or 5° from a vertical line. Dr. Hayden witnessed three eruptions, which lasted from 4½ to 15 minutes; he measured the height of but one, which was over 100 ft. He describes the column as fan-shaped, and says that no water falls from it, but it is resolved into spray which appears to evaporate as soon as formed.
The Giantess.
At 200 yards from the Beehive is the Giantess, a large geyser with an oval aperture described by Langford to be 18 by 25 ft. in diameter. The inside of the tube is corrugated and covered with a whitish silicious deposit. When not in action, no water can be seen in its basin, although its sides are visible to the depth of 100 ft., but a gurgling sound can be heard at a great distance below. When an eruption is about to take place, the water rises in the tube with much spluttering and hissing, sending off vast clouds of steam. It will stand sometimes for several minutes within 40 or 50 ft. of the surface, foaming and gurgling, and spurting jets of hot water nearly to its mouth. When it finally bursts forth, it throws up a column of water the full size of its aperture to the height of 60 ft., and through this rise five or six smaller jets, varying from 6 to 15 in. in diameter, to the height of 250 ft. The eruption, which takes place at irregular intervals, continues for about 20 minutes. Dr. Hayden, who examined it in August, 1872, says the basin measures 23½ by 32½ ft. in diameter, and that the water in it, which is level with the rim, is 63 ft. deep. The only eruption witnessed by him lasted 17 minutes, and the maximum height of the water was 39 ft., the steam rising to 69 ft. After the eruption the water sank 20 ft. in the basin. It probably differs in appearance in different seasons. Further down the river on the same side is the Sawmill geyser, which throws a small stream 10 or 15 ft. high almost uninterruptedly. Near it is the Grand geyser, one of the most powerful in the basin. Within a single basin 52 ft. in diameter are two orifices. One, which is oblong, 2½ by 4 ft., has no rim, and is surrounded for the space of 10 ft, by rounded masses of silica, from a few inches to 3 ft. in diameter, looking like spongiform coral. When not in eruption the water in this spring is quiet and is as clear as crystal. This is the Grand geyser. The second, called the Turban geyser, is 20 ft. from the first. It has a basin of irregular form, 23 by 11 ft. in diameter and 6 ft. deep. The mouth of its tube, which is at one side of the basin, is 4 by 3 ft. wide. This spring, which apparently has no connection with the former, is in a state of agitation as often as once in 20 minutes, and throws its water to the height of from 15 to 25 ft. It is never wholly quiet. The two eruptions of the Grand geyser witnessed by Prof. Hayden's party in 1871 occurred at an interval of 32 hours. In 1872 three eruptions seen by Hayden took place at intervals of 22 and 26½ hours. An eruption is preceded by a rumbling and a shaking of the ground, followed by a column of steam shooting up from the crater, immediately after which the water bursts forth in a succession of jets, apparently 6 ft. in diameter at the bottom, and tapering to a point at the top, to a height of from 175 to 200 ft., while the steam ascends to 1,000 ft. or more. This immense body of water is kept up to this height for about 20 minutes, when it gradually recedes and again becomes quiescent. On the opposite side of the river is the Castle, so called from its resemblance to the ruins of a tower. It stands upon a platform measuring 75 by 100 ft. and 3 ft. in height, above which it rises about 12 ft. Prof. Hayden witnessed three eruptions of this geyser in 1872. The maximum height of the first was 34 ft., and of the second 93 ft.; that of the third was not ascertained. The eruptions lasted each about an hour and 20 minutes.
The Giant Geyser.
The Giant geyser has a rugged crater, like a broken horn, 10 ft. in height and 24 by 25 ft. at the base. The top is about 8 ft. in diameter, with an irregular orifice of 5 or 6 ft. in width. The cone is open on one side, having a ragged aperture from the ground upward. Its discharges are irregular, and continue for irregular periods. When Prof. Hayden saw it in 1871, it played an hour and 20 minutes, throwing the water 140 ft.; but Lieut. Doane, who visited it the year before, states that it played 3½ hours at one time, to a height varying from 90 to 200 ft. The Grotto, the Punch Bowl, the Riverside, the Soda, and the Fan geysers, and numerous others which have not yet even been named, merit notice. There are wonderful groups also on the S. W. side of Shoshone lake, the head of one of the principal forks of the Shoshone or Snake river; and on Gardiner's river are some of the most remarkable springs in the world. The springs in action among the latter are not so numerous nor so powerful as those of the Fire-Hole basin, but are far more wonderful in their calcareous deposits, which exceed even those of the New Zealand geysers. In one place a hill 200 ft. high has been formed in a system of terraces, ornamented with semicircular basins, and with beadwork of beautiful colors on a snow-white ground. These calcareous deposits cover an area of about two miles square. The active springs extend from the margin of the river to an elevation of 1,000 ft. above, the highest being 6,522 ft. above the sea. The geysers of the Fire-Hole basin are from 6,800 to 7,000 ft. above the sea. The valley of the Madison, with its branches, is shut in by high volcanic mountains, gashed with deep gorges, strewn upon their sides and at their bases with fragments of trachyte and obsidian, and covered with tall pines. Between the sources of the Madison and the Yellowstone these mountains rise to 9,000 or 10,000 ft. above the sea. The valley of the Fire-Hole river is covered with the silicious deposits of the springs, and resembles an alkali flat. The bed of the stream is lined with white silica. Beneath this formation are lake or local drift deposits, and still lower basalt. The surface deposit is chiefly geyserite. The most of it is of an opaque white color, but in the lower basin pink specimens are found which are translucent. Some of it is greenish gray and some pearly, like enamel; and it assumes forms similar to those in Iceland. Some have a cauliflower-like form, and break very easily; others are beaded, and others covered with small stalagmitic processes. The texture varies from porous to compact, the most being porous and arranged in layers. The geyser cones are generally compact, and often have an enamel-like coating. A specimen of the white geyserite, of cauliflower form, contained silica 83.83, water 11.02, chloride of magnesium 4; total, 98.85. The water contains very little solid matter. A specimen brought back by Dr. Peale was as clear as when bottled at the springs, showing no deposit; it contained 83525⁄85 milligrammes of solid matter to the litre, consisting mainly of silica; chloride of lime and sulphate of magnesia were present in small quantity, and there was a slight trace of iron.—The geysers of Iceland are treated of in “Letters on Iceland,” by Von Troil (1772); “Travels in Iceland,” by Sir George Mackenzie (1810); “Journal of a Residence in Iceland during the years 1814 and 1815,” by Ebenezer Henderson; “Visit to Iceland in the Summer of 1834,” by John Barrow, jr.; “A Visit to Iceland,” by the Hon. A. Dillon (1840); observations of M. Descloiseaux in Annales de chimie et de physique (April, 1847), and “Philosophical Magazine” (vol. xxx. p. 397); “Tracings of Iceland and the Faroe Islands,” by R. Chambers (1856); “A Yacht Voyage,” by Lord Dufferin (London, 1858); “Iceland, its Scenes and Sagas,” by Sabine Baring-Gould (1863); “The Land of Thor,” by J. Ross Browne (1867); and “A Summer in Iceland,” by C. W. Paijkull, translated from the Swedish by the Rev. M. R. Barnard (1868). For an account of the New Zealand geysers see Neu-Seeland, by Ferdinand von Hochstetter (Stuttgart, 1863). For geysers in the United States, see report of Lieut. G. C. Doane (1871), and the fifth and sixth annual reports of the “United States Geological Survey of the Territories,” by F. V. Hayden (1872 and 1873).