These results differ considerably from those formed in a cloudy sky, and doubtless the difference between experiments carried on under a cloudless sky would differ still more. They do not at all confirm the theory of a decline of 1° of temperature in 300 feet. The Decrease of the Temperature of the Air, at heights exceeding 5000 feet. 8,000 to 9,000 was 2.6 from 8 9,000 to 10,000 was 2.6 from 8 10,000 to 11,000 was 2.6 from 8 11,000 to 12,000 was 2.6 from 6 12,000 to 13,000 was 2.5 from 13,000 to 14,000 was 2.2 from 6 14,000 to 15,000 was 21 from 9 15,000 to 16,000 was 2.1 from 9 16,000 to 17,000 was 1.9 from 9 17,000 to 18,000 was 1.8 from 9 18,000 to 19,000 was 1.8 from 9 19,000 to 20,000 was 1.5 from 9 20,000 to 21,000 was 1.3 from 21,000 to 22,000 was 1.3 from 9 22,000 to 23,000 was 1.0 from 9 23,000 to 24,000 was 1.3 from 2 24,000 to 25,000 was 1.1 from 2 25,000 to 26,000 was 1.0 from 1 6 9 These results follow almost in sequence with those found with a partially clear sky; and together show that a change takes place of 1° of temperature in 139 feet near the earth, and only in 1000 feet at the height of 30,000 feet, and plainly indicates that the decline of 1° of temperature must be abandoned. Treating the observations for determining the degrees of humidity of the air in the same way, the following are the results :— When the Sky was cloudy, saturation being considered as 100, On the earth the degree of humidity was 78 from 5 experiments. At the height of 1,000 the degree of humidity was 76 The law of moisture here shown is an almost uniform state of humidity to the height of 3000 feet, viz. 76·5; then a decrease on the next 1000 feet, and an increase to 83 and 82 at 5000 and 6000 feet. When the Sky was partially Cloudy. On the ground the degree of humidity was 63 from 4 experiments. At the height of 1,000 the degree of humidity was 68 5 At heights exceeding 6000 feet, the following were the results : Ft. At the height of 7,000 the degree of humidity was 64 from 7 experiments. The laws of moisture here indicate a humidity near the ground less by 15 with a partially clear sky, than in a cloudy sky; starting with 63 in the former state on the ground, increasing to 77 at 3000 feet high; then nearly constant to 5000 feet, when it abruptly decreased to 69 and 68 at 5000 and 6000 feet, and then decreased nearly evenly at the rate of 5 in 1000 feet, till at 9000 feet and 10,000 it was 52; the degree then constantly decreased til at a height exceeding 25,000 feet it was less than 10, and it would seem that at higher elevations there was an almost entire absence of water. These seem to be the general laws; but this regular diminution is evidently often interrupted, and strata of moist air may exist, or be passing at different elevations, even up to 20,000 feet, of some thick ness. Electrical State of the Air.-In the ascent on July 17, the air was found to be charged with positive electricity, becoming less in amount with increased elevation, till at the height of 23,000 feet the amount was too small for observation. The instrument was broken in the descent, and was not afterwards used. Time of Vibration of a Magnet.-The general result of all the experiments is, that the magnet vibrates in a somewhat longer interval of time at higher elevations than on the earth. This result is contrary to that found by Guy-Lussac in 1804. On the Propagation of Sound.-From observation made in the different ascents, it was learnt that different notes and sounds pass more readily through the air than others; for instance, the barking of a dog and the whistle of a railway engine have been heard at a height of more than two miles, whilst the shouting of several thousand people cannot be heard at the height of one mile. On the Oxygenic Condition of the Atmosphere.-On July 17, the test papers by Moffat and Schönbein were untinged by colour throughout the journey; and the same result was found during the ascent on July 30th. On August 10, Mr. Glaisher received a letter from Dr. Moffat, of Hawarden, expressing surprise at this result, inasmuch as it has always been received as a theory, that ozone increases in quantity with increased elevation. In consequence of this, Mr. Glaisher went to Dr. Moffat, at Hawarden, and requested him to make some papers, which he did, and these papers were used on August 18, together with some prepared by Messrs. Negretti and Zambra, and some prepared according to Schönbein's formula; and at 22,000 feet the coloration was 4 on a scale whose deepest tinge is 10, whilst those prepared by Schönbein were coloured to 1 on the same scale, and those by Negretti and Zambra were uncoloured; in consequence of this, the preparation of the papers by Messrs. Negretti and Zambra has been stopped. Physiological Observations. —On July 17, before starting, the number of Mr. Coxwell's pulsations were taken, and found to be 74 in one minute; and Mr. Glaisher's were 76 in one minute. At a height of 17,000 feet, Mr. Glaisher's had increased to 100, and Mr. Coxwell's to 84; and on reaching the ground, the number was 76 with both gentlemen. On August 21, no observations were taken before starting. At the height of 1000 feet, the following results were obtained :— The pulsations of Capt. Percival were so weak that he could scarcely count them; whilst those of Mr. Coxwell he considers had increased in strength. From these results it will be seen that diminished pressure exercises a different influence upon different individuals. On July 17, at 19,000 feet the hands and lips were noted as being dark-blue, not the face. At the height of four miles the palpitations of the heart were audible, and the breathing was affected. On August 18, the hands and face were blue at the height of 23,000 feet. On September 5, at the height of about 29,000 feet Mr. Glaisher became unconscious, and at 35,000 feet Mr. Coxwell lost the use of his hands. At 29,000 feet on descending, Mr. Glaisher began to recover, and at 25,000 feet the observations were resumed. The general results of these eight ascents are : 1st. That the temperature of the air does not decrease uniformly with the height above the earth's surface, and consequently the theory of a decrease of 1° of temperature for an increase of elevation of 300 feet must be abandoned. In fact, more than 1° declined in the first hundred feet when the sky was clear, and not so much as 1o in 1000 feet a height exceeding five miles. These experiments are the first to yield any definite information on the subject; more experiments are required to settle the law satisfactorily, but its effect on the laws of refraction will be great all the elevations of the balloon are to a certain extent erroneous, for it has never happened that the mean of the extremities has given the mean of the whole column of air. 2nd. The degree of humidity decreased wonderfully with the height till at above 5 miles there was scarely any aqueous vapour at all. 3rd. That an aneroid barometer can be made to read correctly, to the first place of decimals certainly, and to the second place of decimals probably, to a pressure as low as 7 inches. 4th. That a dry and wet bulb thermometer can be used effectively up to any height on the earth's surface where man may be located. 5th. That the balloon does afford a means of solving with advantage many delicate questions in physics. [J. G.] GENERAL MONTHLY MEETING, Monday, April 6, 1863. The REV. J. BARLOW, M.A. F.R.S. Vice-President, in the Chair. Leveson Francis Vernon Harcourt, Esq. B.A. William Harvey, Esq. F.R.C.S.L. Joseph Norman Lockyer, Esq. F.R.A.S. Paul Julius Reuter, Esq. Octavius Sturges, Esq. Frederick Thompson, Esq. and Robert Wigram, Esq. were elected Members of the Royal Institution. Lieut.-Col. Craven Hildesley Dickens, R.A. John R. Russell, M.D. and John Rivington, Esq. were admitted Members of the Royal Institution. The Special cordial Thanks of the Members were returned to WARREN DE LA RUE, Esq. Ph.D. F.R.S. Manager R. I. for his Present of a Ruhmkorff's Magneto-Electric Induction Coil of a particular construction. SIR RODERICK I. MURCHISON, K.C.B. D.C.L. F.R.S. Manager R. I. having announced his intention of presenting to the Institution annually £20, for the purchase of Scientific Apparatus, the Special cordial Thanks of the Members were returned to him for this additional evidence of his great goodwill towards the Institution. The PRESENTS received since the last Meeting were laid on the table, and the thanks of the Members returned for the same: viz.FROM Imperial Government of France (through M. Rouland, Minister of Public Instruction). Euvres de Lavoisier. Tome II. 4to. 1862. Mémoires Militaires relatifs à la Succession d'Espagne. Tome XI. & Atlas. 4to. 1862. Geological Survey of Great Britain (through Sir R. I. Murchison)—Mineral Statistics, 1860, 1861. 8vo. Memoirs, Six Parts, 1859-62. 8vo. Governor-General of India-Geological Survey of India.-Palæontologica Indica. Part 2, No. 3. 4to. 1862. |