As it is not my object to enter here into the details of baths well known to all travellers in this part of Asia Minor, I shall at once proceed to the description of the sources. The sources of thermal waters near Broosa are seven in number, all situated in a little valley which separates Mount Olympus from Mount Katairli, and they are comprised within the distance of a mile and a half. In the immediate neighborhood of some of these sources, and sometimes in direct proximity, are sources of cool and delightful water that serve to regulate the temperature of the water used in the baths, of which there are as many as twenty private and public. These sources furnish waters of two description, the sulphurous and the non-sulphurous, and I shall commence with a description of the former. THERMAL SULPHUR WATERS. There are two sources of this class of water near Broosa, or rather two places near to each other where it flows out of the mountain, for my examination goes to prove that they are the same water. Their names are Kukurtlu and Bademli-Baghtsche. Kukurtlu Source. The name of the source signifies sulphur. It flows rapidly from the side of the mountain near to its base, through a bed of calcareous tufa, furnishing upwards of twenty gallons a minute, which, along with the water from a cold spring near by, is made to flow through the baths. There is a very sensible odor of sulphuretted hydrogen proceeding from the water of this source, more especially as it issues forth from the mountain, for there is a large amount of gas bubbling through the small reservoir into which the water rises, accompanied with a larger amount of vapor. As the water flows it leaves an incrustation of carbonate of lime, more or less colored with some organic matter. This source is held in particular veneration by the Greeks of the country, who usually assemble here twice a year to commemorate the martyrdom of St. Patrice, which was ordered by the Pro-consul of Broosa, and executed by his being thrown into this almost boiling spring. The country is geologically made up of the older rocks, as granite, gneiss, limestone, &c., a silicious variety of the latter overlying the other two; in some parts, however, the limestone is remarkably pure, and has doubtless furnished to these waters that carbonate of lime so extensively deposited at the base of this part of the mountain in the form of tufa, which, for a mile or two of extent, rises several hundred feet above the plain at the foot of the mountain. Physical Properties.-The water as taken from the source is perfectly clear and transparent, and remains so when kept in well corked bottles, but otherwise a yellow deposit is soon formed which hardly possible to distinguish any variation from symmetry, and such crosses might be taken as proof of a uniaxial character. But on rotating 45°, as in the case of the nitre crystal, we lose the symmetrical form of the cross, which opens out, as represented in fig. 4. This deportment of the cross may be observed when, owing to the depth of color, it is not possible clearly to discern the rings. A method given by Müller* also depends upon this deportment of the dark bars; it consists in rotating the plate of mica when on the table of M. Noremberg's apparatus (the ray being extinguished by the eye-piece); if the mica be biaxial the light is alternately, for every 45° of rotation, transmitted or shut off, if uniaxial, no change is perceived. The image of the cross and rings by this method is so much extended and dimly defined, that the outlines cannot be traced by the eye, and a slight opening-out of the cross is not so readily noticed, even by a change in the intensity of the light, as when its image is contracted and sharpened in outline by the action of lenses. In the following table are given the localities and color of several micas hitherto generally considered uniaxial, but which, on examination with my arrangement, have given evidence of being optically biaxial. 76. Greenwood Furnace, Orange Co., N. Y.; olive green; rhombic plates.† 86. Easton, Pa.; a white silvery mica. 88. Topsham, Maine; fine crimson red. 89. Mount Vesuvius; dark green, 105. 102. 66 second specimen. Another specimen; clearly biaxial. A thicker plate of specimen 101; clearly biaxial. transparent, with delicate shade of green; banded with bands of a deep green, meeting at angles of 60°. *Lehrbuch der Physik und Meteorologie, Braunschweig, 1844, p. 588. + Greenwood furnace is in the town of Monroe, and this is the Monroe mica, analyzed by von Kobell (Kastn. Arch., xii, 29, and Dana's Min., 3d edit., 360) and pronounced by him on optical grounds to be uniaxial, it giving a symmetrical cross. It afforded the chemical formula R3 Si + (Al, Fe) Si, corresponding to the oxygen ratio for the protoxyds, peroxyds and silica 1:1:2. The exact ratio as worked out by Rammelsberg is 104: 98: 20-78, while the Vesuvian mica gave 101: 100: 20-65, and one from Bodenmais 10-25: 1096: 21-23. The ratio is in fact the general ratio of the so-called “hexagonal" micas or Biotites. In the Greenwood furnace mica, we have evidence therefore that one at least of these Biotites is not hexagonal; and the same we believe true for some of the "hexagonal" Vesuvian micas. The impor tance of a revised crystallographic examination of these micas is hence obvious. The mica of Greenwood furnace is of a blackish green color, and occurs usually in very acute oblique prisms, often of very large size; angle of prism (M: M) 71° to 72°, it being oblique from an acute edge, and not from an obtuse edge as in ordinary biaxial mica. The angle between the base and a lateral plane (P: M) 18 66°-67° and 103° to 114°, according to the writer's measurement. The replacement of the acute solid angle reduces the form to a rhombohedron with a basal cleavage plane, and thus it was taken by von Kobell. The faces of the crystals are so imperfect that the discrepancies obtained are usually one degree, on similar parts of the same crystal. Another Monroe mica (No. 81 above) is the only other mica which could possibly have been Kobell's, and that too is proved by Mr. Blake to be biaxial. J. D. D. 103. Mount Vesuvius; from same specimen as 102, but thicker; biaxial. 104. 44 66 142. from same specimen, still thicker; gives good elliptical image. beautiful green, like No. 101, is in small hexagonal crystals and associated with Idocrase. 111. Franklin Furnace, Sussex Co., N.J.; deep copper red; G.J. Brush to B. Silliman, Jr. 109. St. Jerome, Canada; coppery, reddish; angle, estimated 10°. 114. Moors Slide, Ottawa, Canada; dark bottle green; T. S. Hunt to B. Silliman, Jr. 116. St. Lawrence Co., N. Y.; dark brownish green; opaque, over 062 mm. thick. 84. Hammond, St. Lawrence Co., N. Y.; rich smoky yellow; from Saml. W. Johnson. dark brownish red; black by reflected light. 68. 106. Gouverneur, N. Y.; (boulder) dark brown. 81. Monroe, Orange Co., N. Y.; dark green. 108. 46 107. Locality 112. Locality dark bottled-green; from S. R. Horton to B. Silliman, Jr. ? Cambridge Cabinet; rich brown; in beautiful rhombic plates; ? Cambridge Cabinet; deep green; like Greenwood Furnace mica. 63. Moriah, Essex Co., N. Y.; fiery red; Lederer Cabinet; angle measurable. 139. Warwick, Pa.; olive green (brownish); angle estimated over 10°; this much resembles the Vesuvius specimens, Nos. 102 and 103. With the exception of the dark micas mentioned in the following table, I have not yet examined any that do not give evidence of being optically biaxial; and, it is probable, that these exceptions would give the modifications of the cross, &c., if their dark color did not make it impossible to observe them in plates sufficiently thick. But if biaxial, the angle for the mica of Sussex, New Jersey, No. 115, must be very small. 98. Locality 83. Locality dark olive green; resembles No. 81. Yale Coll. Cabinet; color intensely green. 115. Sussex Co., N. Y.; dark green; opaque when in plates over 222 of 1 mm. thick. 113. Locality -N. Y. Lyc. Nat. Hist.; opaque in plates over 042 mm. thick. 148. Middletown, Ct.; very dark green. 146. N. Y. Island; very dark olive-green; in granite veins traversing gneiss. 147. To Prof. B. Silliman, Jr., I am indebted for the free use of his specimens for these investigations: the biaxial character of many of them was suspected by him, when he first examined them, as is mentioned in his communication in this Journal, vol. x, November, 1850. In specimens of mica referable to the species Phlogopite, having the inclination of the resultant axes between 50 and 20°,when the thickness is so much reduced that the systems of rings around poles are not distinctly separated, the angular inclination of the axes cannot be determined in the ordinary manner. Further observations upon this point I reserve for a future com munication. SECOND SERIES, Vol. XII, No. 34.-July, 1851. 2 ART. III-On some of the Thermal Waters of Asia Minor; by Dr. J. LAWRENCE SMITH, of New Orleans, Prof. Chem. in the University of Louisiana. Part I.-The Thermal Waters of Broosa. THERE are few countries where Thermal Waters are so numerous, and cover so extensive a surface as in Western Asia Minor; many of them still bear marks of the estimation in which they were held by the ancient Romans and Greeks for the purpose of supplying their baths. Owing to the difficulty of obtaining proper vessels or corks at or near the springs, coupled with the risk of breakage by the necessary transportation on the backs of horses over rough and mountainous roads, travellers have been deterred from collecting these waters for the purpose of analysis. In my travels through certain parts of this country, I took along with me bottles and corks, and collected between twenty and thirty specimens of different localities, some of them in considerable quantity; and of that number fifteen or sixteen have arrived safely to my laboratory, where most of them have been already examined. In my remarks upon them I will first allude to the thermal waters of Broosa or Prusia, which are the most important at the present day, and the most accessible from Coustantinople. The spot itself is hallowed by many interesting historical associations. The city was founded by Hannibal during a friendly visit which this great Carthagenian general made to Prusias, the king of Bythinia, whose name was given to it. Like all other cities of so ancient date, it has gone through many changes, passing successively into the hands of the Greeks, Romans, and Turks. Since 1326 the Turks have continued masters of this part of Asia Minor, it having been conquered by Osman just prior to his death, for many years after which event it remained the capital of the Ottoman empire. Broosa is readily reached from Constantinople by a steamer that goes from this latter place to Modania, on the gulf of the same name, about seventy miles from Constantinople. From Modania a ride of about twenty miles on horseback brings you to Broosa, at the foot of the Bythinian Olympus. The warm baths of this place have been celebrated from the earliest epochs, and the visit of Constantine with his wife in 797, is recorded in history as having resulted favorably in restoring the latter to health. And at a still later period Sultan Soleman the Great visited these baths on account of an attack of gout, and to commemorate his cure he had a large dome constructed over the source to which he attributed the beneficial effects derived by him; the dome still stands. As it is not my object to enter here into the details of baths well known to all travellers in this part of Asia Minor, I shall at once proceed to the description of the sources. The sources of thermal waters near Broosa are seven in number, all situated in a little valley which separates Mount Olympus from Mount Katairli, and they are comprised within the distance of a mile and a half. In the immediate neighborhood of some of these sources, and sometimes in direct proximity, are sources of cool and delightful water that serve to regulate the temperature of the water used ⚫ in the baths, of which there are as many as twenty private and public. These sources furnish waters of two description, the sulphurous and the non-sulphurous, and I shall commence with a description of the former. THERMAL SULPHUR WATERS. There are two sources of this class of water near Broosa, or rather two places near to each other where it flows out of the mountain, for my examination goes to prove that they are the same water. Their names are Kukurtlu and Bademli-Baghtsche. Kukurtlu Source. The name of the source signifies sulphur. It flows rapidly from the side of the mountain near to its base, through a bed of calcareous tufa, furnishing upwards of twenty gallons a minute, which, along with the water from a cold spring near by, is made to flow through the baths. There is a very sensible odor of sulphuretted hydrogen proceeding from the water of this source, more especially as it issues forth from the mountain, for there is a large amount of gas bubbling through the small reservoir into which the water rises, accompanied with a larger amount of vapor. As the water flows it leaves an incrustation of carbonate of lime, more or less colored with some organic matter. This source is held in particular veneration by the Greeks of the country, who usually assemble here twice a year to commemorate the martyrdom of St. Patrice, which was ordered by the Pro-consul of Broosa, and executed by his being thrown into this almost boiling spring. The country is geologically made up of the older rocks, as granite, gneiss, limestone, &c., a silicious variety of the latter overlying the other two; in some parts, however, the limestone is remarkably pure, and has doubtless furnished to these waters that carbonate of lime so extensively deposited at the base of this part of the mountain in the form of tufa, which, for a mile or two of extent, rises several hundred feet above the plain at the foot of the mountain. Physical Properties.-The water as taken from the source is perfectly clear and transparent, and remains so when kept in well. corked bottles, but otherwise a yellow deposit is soon formed which |