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ples from the Coast Survey observations. From this publication, it appears that the latitude is given, by a single night of observation, to the fraction of a second of arc, and that in four or five nights it can be determined with the minutest accuracy of which astronomical measurement is susceptible. The instrument employed is of simple construction, and of little cost, while its accuracy must render it available for some most delicate geodetic and geological researches. It is not impossible that, in the hands of a skilful geologist, it may aid in determining the various densities of the crust of our globe, and thereby serve as a divining-rod for detecting its internal wealth ; and it may thus give birth to a new species of practical astrology.
“ The use of Morse's magnetic telegraph for the determination of astronomical differences of longitude was too obvious to escape early notice, but it was reserved for the Coast Survey to ascertain its practicability as an exact method. This has been done by a series of refined and careful observations, made under the direction of Mr. Sears C. Walker, from which it appears that differences of longitude thus determined can be employed in the measurement of the earth in a direction perpendicular to the meridian. This conclusion is of great importance in reference to the survey of a coast which deviates from the arc of a meridian so much as that of the United States. The introduction of clockwork into the magnetic operations will undoubtedly contribute to their accuracy, although it remains to be seen which of the different plans that have been devised will be the preferable one.
“Professor Bache's method of employing the great theodolite in the primary triangulation must command the admiration of experienced observers for its conscientious accuracy, and its skilful and faithful determination of every correction and every source of error. His measured angles have rewarded his patience and perseverance, by submitting to the usual tests with a uniform exactness which has never been surpassed, and which proves that one fifth of a second of arc is the greatest error to which any one of his angles is liable. This extraordinary accuracy is not attained at any sacrifice of time; but, on the contrary, the present Superintendent has completed the observations at each station in much less time than was required by his predecessor, because he has rejected an unnecessary and injudicious rule in regard to the selection of days of observation.
"All the other portions of the field work, whether of the reconnoissance, of the primary, secondary, or tertiary triangulation, or of the
topography or hydrography, and also the office work, are distinguished for the same scrupulous regard to accuracy and despatch. The observations, indeed, which are made in the field by one set of officers, are reduced and plotted by others in the office, so that there can be no danger of any deception, and every thing must be as good as it appears. The observations of the Superintendent himself are not excepted from this ordeal.
“ The committee cannot pass from this head of their inquiry without expressing their commendation of the beautiful execution of the charts, and of the wise liberality with which they are furnished to navigators at a trifling cost.
“2. The survey has already embraced a very extensive portion of the coast, and numerous discoveries have been made of the highest importance to navigation. “The field or office work of the survey has been carried into every State on the Atlantic and the Gulf of Mexico, except one.' Every year results have been obtained of a mercantile value incomparably superior to their cost, and which would be sufficient to pay, again and again, for the whole year's work. To say nothing of the many important discoveries of useful channels, or of hidden and unknown dangers, in Long Island Sound, in Buzzard's, Massachusetts, Chesapeake, and Mobile Bays, who can estimate the value of Gedney's Channel* to New York harbour ? of the determination of the changes in the main ship-channel, which have been so gratefully acknowledged by the Chamber of Commerce of New York ? or of Blake's new channel in Delaware Bay ? or of Davis's discoveries of the shoals in the vicinity of Nantucket, for which the insurance-offices of Boston and New York have acknowledged their obligation? Is not each of them separately worth the whole amount which has been expended upon the work? But leaving these remarkable discoveries to the merchants and sailors who are most competent to appreciate them, your committee would draw the attention of the Academy to some other results, of a less practical, but no less scientific, interest.
“3. From the variety of his scientific attainments, the attention of the Superintendent has been readily drawn to all classes of observations which would conduce to the progress of science, and which could be made by himself or any of his parties without obstructing their other duties. Thus the abstruse problem of the figure of the earth will undoubtedly receive its due consideration when the primary triangula
* Gedney's and Blake's Channels were discovered during the administration of Mr. Hassler.
tion is completed; and also the local variations of figure in connection with those differences of internal density, the detection of which is already to be enumerated as one of the scientific discoveries which have been made upon the survey.
“ The intricate problem of the tides, also, which is still so defective, notwithstanding the labors of Laplace, Airy, Lubbock, and Whewell, will undoubtedly receive new development from the observations of the survey, and the laws of the tides upon the American coast will be ascertained.
“ The exploration of the Gulf Stream, which was commenced by Lieutenant Davis, and so indefatigably pursued, even to the sacrifice of his life, by the lamented George M. Bache, has led to results which are of profound scientific importance; and the deep-sea soundings, which have been examined by Professor Bailey, are also replete with interest to the naturalist.
“4. Your committee have few data for arriving at any definite con. clusion with regard to the extent of the economy with which the survey has been conducted. They are not, however, aware of any objection to the comparison which has been instituted by the Superintendent with the surveys of the Land Office, and which is very favorable to the Coast Survey. There is certainly no appearance of waste or extrava. gance in any respect; there are no excessive salaries, no idle attachés, nor any apparent disposition to pay too much for services rendered. There seems, on the contrary, to be an anxious desire to husband the appropriations of Congress, and to derive from them the largest possible return of valuable results. It is especially deserving of notice, that the Superintendent has manifested the wisest and most unselfish economy in asking for large appropriations, in order that he may press forward the work as rapidly as possible to its final completion.
“ In conclusion, it is the deliberate opinion of the committee, that the present Superintendent of the United States Coast Survey has, by his able and judicious, his energetic and economical administration of this great national work, raised it to the highest state of successful activity and deserved popularity, and that he has thereby fulfilled the high expectations which were raised at his appointment. “ All of which is respectfully submitted by
Professor Lovering, in the absence of the chairman of the Rumford Committee, read the following report on a communication of Mr. James Frost, which was referred to that committee.
“ The Rumford Committee, having examined the paper submitted by James Frost, Esq., of Brooklyn, New York, and entitled, “ Description of the Causes of the Explosion of Steam-boilers, and of some newly discovered Properties of Heat, and other Matters : for the Purpose of showing that the Application of Steam for the Production of Motive Force is susceptible both of immense Improvement and Economy,' respectfully report:
“The chief points which the author claims to have established are,
“ 1st. That steam of 212° Fahr., heated, out of contact with water, to 216°, doubles its volume ; and heated to 228°, increases its volume threefold.
“2d. That steam of low tension, heated to somewhere about 650°, is converted into another body, which the author calls óstame,' and which, under favorable circumstances, becomes six times as effective as steam not so beated.
“As, in the view of the author, the question of discovery rests upon the truth of the first of these two propositions, the attention of the committee has been particularly directed to its consideration. To this end, the apparatus employed by Gay-Lussac in his determinations of the tension of aqueous vapor at different temperatures was constructed, and a series of experiments made upon steam heated, out of contact with water, from the boiling point to 2330.6. The results arrived at were as follow.
“A volume of steam at 212° Fahr., measuring 15.80 cubic centimetres, or 1580 parts, heated to 216°, became 1600 parts, and heated to 228°, became 1630 parts. According to Mr. Frost, 1580 parts at 212° should have become 3160 parts at 216°, and 4740 parts at 228°. In tabular form we have, at
228° 1630 4740 3110 “The results for higher, intermediate, and lower temperatures are VOL. II.
given in the accompanying table. The whole expansion of the steam, when heated from 212° to 228°, was a little more than one thirtieth of its volume at 212o. According to Mr. Frost, it should have been more than ninety times as great as the committee found it to be.
“ The experiments of the committee were made with steam under a pressure ranging from 24 to 244 inches of mercury, that is, under less than atmospheric pressure. This condition could not influence the result unfavorably to the view of Mr. Frost, since the less the pressure, the greater is the expansion with a given elevation of temperature.
233.6 232.7 231.8 230.9 230.0 229.1 228.2 227.3 226.4 225.5 224.6 223.7 222.8 221.9 221.0 220.1 219.2 218.3 217.4 216.5
108.5 108 107.5 107 106.5 106 105,5 105 104.5 104 103.5 103 102.5
214.7 213.8 212.9 212.0 211.1 210.2 209.3 208.4 207.5 206.6 204.9 203.0 201.2 199.4 197.6 195.8 194.0 158.0
“ The committee deem it unnecessary to consider farther the claims of the alleged newly discovered properties of heat, as set forth in the pamphlet of Mr. Frost.
E. N. HORSFORD, JOSEPH LOVERING, DANIEL TREADWELL, BENJAMIN PEIRCE.”
Mr. Foster, of the United States Survey of the Mineral Lands of Lake Superior, being present by invitation, read the subjoined paper.