_Powell, B._, on the interference of light, xxxviii, 107.

----, on refractive indices, xxxviii, 107.

----, on the wave theory, xxxviii, 108.

----, on radiant heat, xl, 313.

----, on certain cases of elliptically polarized light, xliv, 171.

----, on the elliptic polarization of light, reflected from various

substances, xlvi, 390.

Power of horses, xxi, 167.

Pozzuolana, iv, 373.

Practical Tourist, review of, xxiii, 213.

Prague, statistics of, ix, 184.

Prairies, origin of, _R. W. Wells_, i, 331.

----, ---- and extension of, _R. Nutt_, xxiii, 40.

---- of the West, _C. Atwater_, i, 116.

---- and barrens of the West, _A. Bourne_, ii, 30.

---- of Alabama, _W. W. McGuire_, xxiv, 187; xxvi, 93.

---- formation of Opelousas an Attakapas, _W. M. Carpenter_, xxxv, 344.

----, observations on, _G. Jones_, xxxiii, 226;--dry prairies, 226;

comparison with Holland, 228.

---- of Ohio, xxxiii, 230.

---- of Texas, _J. L. Riddell_, xxxvii, 212.

----, Hog-wallow, of Texas, notice of, xxxix, 211.

Prase in Massachusetts, i, 344.

---- in Rhode Island, viii, 226, 230.

---- in Pennsylvania, viii, 238.

Precession of the equinoxes, remarks on, vii, 323^f; viii, 132, 139.^f

---- ----, constant of, _O. Struve_, xlvii, 91.

Precipitate, purple, of silver and gold, xxii, 198.

Prehnite, _L. P. Walmstedt_ on, ix, 378.

----, datholite, &c. at Kewenaw Point, Lake Superior, _C. T. Jackson_,

xlix, 87.

----, in Connecticut, i, 50, 135; ii, 232; vi, 223.

----, in Massachusetts, i, 114; iii, 364.

----, in New Jersey, ii, 183, 191, 195, 197; v, 239; xl, 69; xliv, 58.

----, in Pennsylvania, x, 220.

Premiums by the French Academy of Sciences, for 1827, xiv, 380, 389.

---- ---- ----, for 1831, xxii, 194.

---- offered by the Society for the Encouragement of National Industry,

France, 1821, 1822, iv, 192.

---- ---- ----, for 1832-34, xxii, 359.

----, for Mechanical Arts, iv, 192.

----, for Chemical Arts, iv, 192.

----, for fabrication of Russian leather, iv, 193.

----, for Economical Arts, iv, 193.

----, for useful inventions in agriculture, xviii, 382.

----, for chemical and medical discoveries, xxii, 194.

----, scientific, xxiv, 210.

----, see farther under _Medals_ and _Prizes_.

Prenanthes aphylla, v, 299.

Preservation of objects in Natural History, iv, 198.

---- of specimens of animals, directions for, xii, 271; xix, 52.

---- ---- ibid, with arsenical soap, xix, 53.

---- of zoological collections from insects, _T. S. Trail_, xv, 167.

---- of animal and vegetable substances from insects, _J. Macartney_,

xxxi, 367.

---- of specimens, new mode of, _J. L. Riddell_, xxxv, 338.

---- of eggs, Scotch method, xxvi, 188.

---- ---- for cabinets, xxi, 161.

---- of insects, _T. Roger_, xix, 213.

---- ----, xix, 56; xxi, 162.

----, of freshwater shells, xlii, 391.

---- of Echini with the spines, xxix, 353.

---- of skins, xxvi, 188.

---- of fish skins for museums, xxxvi, 196.

---- of anatomical preparations, vi, 384.

---- of skeletons, xix, 57.

---- of animal bodies, new mode of, by petrifaction, _G. Segato_,

xxix, 359.

---- of animal preparations, by Gannal's new process, xl, 194.

---- of animal substances, salt for, xxx, 183.

---- of crystalline lenses, xxvi, 216.

---- of dead bodies, i, 307.

---- of meats, &c. by Appert's process, xiii, 163.

---- of fruits without sugar, method of, xv, 381.

---- of substances by alkalies, xxiii, 383.

---- of cordage, &c. from moisture, xxiii, 199.

---- of firemen against fire and flame, xviii, 177; xx, 96.^f

---- of grain from mice, vii, 378.

---- of timber by pyrolignite of iron, _Boucherie_, xl, 213.

---- of the Royal George, xl, 213.

---- from rust, a mode of, by means of caoutchouc, vi, 398.

---- of iron from rust, xix, 203; xxi, 150; xxii, 382;

xxiii, 199, 383.

_Presl_, notice of the Genera Fileacearum of, xxxix, 174.

Press, botanical, _J. Locke_, xxx, 54.^f

----, printing, see _Printing_.

Pressure in the ocean at great depths, see _Ocean_.

----, atmospheric, see _Barometrical_.

---- on the human body, variations of, and apparatus for withdrawing,

xxxiv, 30.

----, effect of instantaneous, as compared with accumulative,

_C. Bonnycastle_, xl, 32.

Price of labor and subsistence in some parts of Europe, xxxvi, 176.

_Priestley, J._ philosophical character of, _W. Henry_, xxiv, 28.

----, discoveries by, xxiv, 30.

Primula farinosa, iv, 59.

_Prince, James_, on the sea-serpent, ii, 154.

_Prince, John_, memoir of, xxxi, 201.^f

_Prince, W._, a fruit, between the Spanish chesnut and the Maryland

chinquapin, iii, 77.

Prince Regent's Inlet, geology of, xvii, 10.

Princeton, battle of, painted by J. Trumbull, xxxix, 231.

Principia of Newton, new edition of, vi, 379.

---- ----, review of, xi, 238; xii, 28, 330; xiii, 311.

Prinos coriaceus, v, 293.

Printing on zinc, x, 388.

----, a mode of stereotyping by Senefelder, xi, 386.

----, invention of stereotyping, xvii, 161.

----, stereotype, original papers by _C. Colden_ and _B. Franklin_

on, xxiv, 319.

---- designs, new mode of, vii, 191.

----, anastatic, xlix, 401.

---- press, improvements in, by J. I. Wells, iii, 311.^f

---- ----, inking machine, Wood's, xxiii, 103.^f

---- ---- for the blind, v, 385.

Prisons, Society for the Amelioration of, iii, 374.

Prizes offered by the Royal Society of London, xxv, 412.

Prize given by the Royal Society to _J. F. W. Herschel_, for a paper

on double stars, xxv, 412.

---- respecting the ammoniacal azoturet of potassium, offered by the

St. Petersburg Academy, xxv, 205.

----, the Montyon, presented, xxv, 189.

----, the De Lalande, given to E. Sabine, xii, 194.

----, ----, xxv, 190.

---- of the Academy of Sciences, xiv, 380, 389; xxii, 194.

Problems, diophantine, xxxi, 156.

----, dynamical, new solutions of, xxxviii, 106.

Producta, see ZOOLOGY, _Mollusca_.

Profile mountain, New Hampshire, _M. Field_, xiv, 64^f; xxxiv, 122.

Pronouns, nature of, explained, xxxiv, 337.

Proportions, definite, in Chemistry, _D. Olmsted_, xii, 1.

Prospect Hill, East Haven, Ct., scenery of, vii, 3.

Proteus of the North American Lakes, _S. L. Mitchill_, iv, 181;

vii, 68.^f

----, _D. H. Barnes_, xi, 285.

Protococcus kermesinus, analogous to red particles in blood, xxxvi, 206.

_Prout, W._, analysis of starch sugar, xxxv, 299.

Providence Franklin Society, xviii, 195.

---- tornado, _R. Hare_, xliii, 137.

---- ----, _W. C. Redfield_, xliii, 263.^f

Prunnerite, new mineral species, xx, 197.

Prussia, population of, ix, 184.

----, universities of, xx, 388.

Prussian travellers, vii, 195.

Prussiate of potash, red, deoxidation of, _C. F. Schönbein_, xlix, 203.

---- ----, manufacture of, at Glasgow, _T. Thomson_, xli, 49.

Prussian blue, new mode of preparing, viii, 380.

---- ----, researches into the manufacture of, xv, 178.

---- ----, formation and nature of, xviii, 332.

---- ----, manufacture of, at Glasgow, xli, 50.

Prussic acid, _F. Magendie_ on, ii, 81.

---- ----, memoir on, _B. L. Oliver_, iii, 182.

---- ----, ----, _Orfila_, xviii, 157.

---- ----, effect of muriatic and sulphuric acids on, xviii, 146.

---- ----, extraordinary production of, _A. A. Hayes_, xviii, 201.

---- ----, preservation of, xvi, 260.

---- ----, apparatus for the evolution of, _R. Hare_, xxix, 244.^f

---- ----, impurities of, xix, 70.

---- ----, cases in which administered, iii, 187.

---- ----, efficacy in asthma, vi, 366.

---- ----, action of, on a horse, xii, 385.

---- ----, effects on vegetation, x, 190.

---- ----, chlorine an antidote for, xvii, 174; xxi, 157.

Pseudomorphine, a new vegetable extract, xxx, 179.

Pseudomorphism, observations on, _J. D. Dana_, xlviii, 81, 397.

Pseudomorphous minerals, account of, in a review of _J. R. Blum's_

treatise, xlviii, 66.

---- (crystallized) steatite, in Massachusetts, _C. Dewey_, iv, 274;

v, 249; vi, 333; viii, 51.

---- steatite, having the form of quartz, scapolite and spinel,

xxi, 320.

---- steatitic hornblende, analysis of, _L. C. Beck_, xlvi, 35.

---- quartz, at Southampton lead mine, vi, 214; ix, 249.

---- ----, in Pennsylvania, x, 223.

---- granite, vii, 22.^f

Pseudomorphs, siliceous, in Hampshire Co., Mass., xii, 256.

Pseudo-volcanoes of the Upper Missouri, xlv, 154.

Psora, use of chloride of lime in, xvi, 395.

Pudding stone of Mount Toby, Mass., vi, 8, 69.

Pulkova Observatory, xlvii, 88.

Pulmonary consumption, work on, _S. G. Morton_, noticed, xxv, 424.

Pultowa, monument of, iii, 379.

Pumice, floating, xx, 161.

---- at the Azores, iv, 259.

---- of the Mississippi, iii, 247.

---- of the Missouri and Mississippi rivers, due to pseudo-volcanoes,

_J. N. Nicollet_, xlv, 154.

Pump, by steam, xvi, 181.

----, air, see _Air pump_.

Purple of Cassius, ii, 350; xx, 192; xxviii, 145; xlviii, 192.

_Pursh, F._, notice of the herbarium of, xl, 11.

----, botanical excursions of, xlii, 10.

----, notice of, ix, 269.

Putnam's rock, v, 37.

Putnam Hill, section of, xxix, 30.^f

Putrefaction, animal, xviii, 397.

---- of stagnant water, prevented by animal charcoal, x, 189.

_Puvis_, essay on lime as a manure, xxx, 138.

Pyrargillite, analysis and description of, _Nordenskiöld_, xxvi, 387.

Pyrenees, geological notice of, ix, 23.

----, botany of, remarks on, xiv, 377.

Pyrites, arsenical, in New Jersey, v, 244.

----, copper, see under _Copper_.

----, iron, origin of, in fossils, xxviii, 293.

----, ----, occurrence of, in fossiliferous rocks, xxxi, 74.

----, ----, investing quartz, vegetable stalks, &c., _L. Lyon_,

xii, 162.

----, ----, in a peat field, _J. T. Plummer_, xliv, 312.^f

----, ----, specific gravity of, xix, 388.

----, ----, cause of decomposition of, xix, 387.

----, ----, of Rossie, complex crystal of, xlvi, 36.^f

----, ----, in Connecticut, i, 316; v, 44; vii, 56; x, 13; xxxiii, 160.

----, ----, in Georgia, xxiv, 9.

----, ----, in Kentucky, iii, 233.

----, ----, in Massachusetts, viii, 54; x, 13, 18; xxii, 51.

----, ----, in Missouri, iii, 67.

----, ----, in New Hampshire, xviii, 129, 131.

----, ----, in New Jersey, v, 28.

----, ----, in New York, v, 12; xix, 224; xxv, 350; xxviii, 172.

----, ----, in North and South Carolina, iii, 3; v, 262; xli, 183.

----, ----, in Ohio, xvi, 156, 157.

----, ----, in Pennsylvania, iv, 4; viii, 239; x, 222; xiv, 5, 6, 8, 13.

----, ----, in Vermont, i, 115; iii, 76, 326; vi, 245.

Pyrochlore, analysis of, _F. Wöhler_, xviii, 392; xliii, 35.

---- of Chesterfield, Mass., _J. E. Teschemacher_, xlviii, 395.

----, identical with microlite, _J. E. Teschemacher_ and _A. A. Hayes_,

xliii, 33.

---- and microlite, not identical, _C. U. Shepard_, xliii, 116;

xlviii, 177.

----, analysis of, xlvi, 163.

Pyro-citric acid, new, vii, 187.

Pyro-gallic acid, _J. Pelouze_, xxviii, 126.

Pyrogenic acid, new, xxxiv, 206.

Pyroligneous acid, ii, 340; v, 188; ix, 201.

---- ----, purified by animal charcoal, xiii, 175.

---- ----, medical use of, ix, 201.

Pyrometer, steam, _W. R. Johnson_, xxii, 96.^f

Pyromorphite, or phosphate of lead, _C. Kersten_, xxii, 307.

Pyrope at Brimfield, Mass., vi, 222.

Pyrophorus, explosion of, x, 366.

----, new, from tartrate of lead, ix, 207.

----, remarks on, _Gay Lussac_, xvii, 176.

----, new, _R. Hare_, xix, 173.

Pyrophyllite, xviii, 392.

Pyrophysalite, ix, 21.

Pyrotechny, history of, vii, 137.

----, _J. Cutbush_ on, ix, 173.

Pyroxene, see _Augite_.

Pyrrhite, xlvii, 340, 418.

Q.

Quackery, medical, iv, 390.

Quadrant, _T. Godfrey_, the inventor of, xxxv, 389.

Quadrupeds about Richmond, Indiana, xlvi, 244.

----, habits and anecdotes of, xlvi, 237, 243.

----, see farther under _Zoology_.

Quantity of matter, effect of, on affinity, xvi, 234.

Quarantine, high temperatures disinfecting and affording a substitute

for, _W. Henry_, xxi, 392.

Quartz, on certain cavities in, _W. L. Atlee_, xxxv, 139.^f

----, from Elba, containing water, iv, 27.

----, American, containing liquids, ii, 14; ix, 246; (and coal) xl, 83.

----, naphtha in, _C. Dewey_, i, 345.

----, soft crystal of, v, 394.

----, gelatinous, _Guillemin_, xiv, 391.

---- crystals, distorted, xlvi, 365^f, 366.^f

---- ----, in Canada, viii, 63.

---- ----, in Connecticut, i, 135; v, 41, 45;

--(rose) i, 238; iv, 54; vi, 213, 251.

---- ----, in Maine, (smoky) xiii, 374; (rose) xviii, 297.

---- ----, in Massachusetts, i, 112, 113, 136; (rose) i, 116; vi, 247.

---- ----, in Missouri, iii, 67.

---- ----, in New Hampshire, (rose) xvii, 355; (smoky) xxxiv, 114.

---- ----, in New Jersey, ii, 197.

---- ----, in New York, i, 241; ii, 13; iii, 233; iv, 44; vi, 247;

ix, 44.

---- ----, in North or South Carolina, iii, 5.

---- ----, in Pennsylvania, i, 237; ix, 45; x, 222; xiv, 5.

---- ----, in Rhode Island, viii, 230; ix, 46; xl, 185.

---- ----, in Vermont, vi, 249.

---- ----, near Lake Superior, smoky and amethyst, vii, 48.

----, pseudomorphous, in Massachusetts, at Southampton, vi, 214;

ix, 249; xii, 256.

---- ----, in Pennsylvania, x, 223.

----, imitated by steatite, in Massachusetts, v, 249; vi, 333; viii, 51.

----, ---- ----, in New Jersey, xxi, 320.

---- rock of western Massachusetts, viii, 16.

---- veins, origin of, _G. Bischof_, xlix, 396.

Quebec, cement of the Castle Rock, _F. H. Baddely_, xxviii, 367.

----, Literary and Historical Society, transactions of, xvii, 412;

xxv, 211.

Queries, geological, proposed by the geologists of the New York State

survey, xxxiii, 124.

---- relative to mineral veins, xxxiii, 135.

Quicksilver mines of Spain, xxviii, 17.

---- ---- of Idria, xxix, 219.

_Quinby, A. B._, investigations relative to the blowing machinery of

blast furnace, xii, 128.

----, examination of the maximum and minimum effects of machines,

xii, 346.

----, on crank motion, vii, 316^f; ix, 317; x, 203; xi, 335; xi, 338^f;

xii, 344^f; xiii, 73, 356.

----, on pitchback and breast wheels, xi, 333.

----, on high and low pressure boilers, ix, 313.^f

----, on the spiral of Archimedes, ix, 316.^f

----, new demonstrations on the theory of the overshot water-wheel,

ix, 304^f;

Quinine, preparation of, xlvii, 196.

----, remarks upon, xx, 52.

----, sulphate of, frauds in, x, 386.

----, ----, mode of detecting its adulteration with sugar, xiii, 400.

----, manufactures of, in France, xiv, 390.

Quinoline, xlvii, 196.

R.

Races of men, enumeration and characters of, _S. G. Morton_,

xxxviii, 342^f; xlvii, 206.

---- ----, stature of, xxii, 357.

----, Indian, of America, characteristics of, _S. G. Morton_,

xxxviii, 345, 347, 360^f; xlvii, 408.

---- of the Andes, ancient, xxix, 358.

----, Peruvian, characteristics of ancient and modern, _S. G. Morton_,

xxxviii, 361^f, 365.^f

Radiant heat, transmission of, _M. Melloni_, xxvii, 228.

---- ----, _B. Powell_, xl, 313.

Radiation of heat, _A. D. Bache_, xxx, 16; xxxiv, 39.

---- ----, apparatus for illustrating, xxviii, 320.^f

Radius of the earth, xxxi, 234.

_Rae, J._, balloon raised by solar heat, xxxiii, 196.

_Rafinesque, C. S._, progress of vegetation near Philadelphia, i, 77.

----, on atmospherical dust, i, 397.

----, on the genus Flœrkea, i, 373.

----, new species of grass, Diplocea barbata, i, 252.

----, Cylactis, Nemopanthus and Polanisia, three genera of New York

plants, i, 377.

----, description of the Xanthium maculatum, i, 151.

----, new genus (Exoglossum) of freshwater fish, i, 155.

----, Mustela vulpina, new species, i, 82.

----, Scytalus cupreus, or copper headed snake, i, 84.

----, sponges on Long Island shores, i, 149.

----, notice of the works of, xxix, 393, 394.

----, ---- of zoological writings of, _S. S. Haldeman_, xlii, 280.

----, ---- of the Botanical writings of, xl, 221.

Railroads in Austria, xx, 174.

---- in the United States, extent of, _J. Henry_, xxxiii, 296.

----, Hudson and Mohawk, account of, _S. D. Bloodgood_, xxi, 141.

----, graduation of Mohawk and Hudson, xxi, 385.^f

----, Baltimore, method of clearing the snow from, xx, 166.^f

---- curves, _T. Gorton_, xxvii, 131.^f

----, elevation of, required for rails, over roads of a certain

curvature, _J. Thomson_, xxii, 346.^f

----, inclined planes in the construction of, _J. Thomson_, xxiii, 107.

----, turnouts in, with flexible moveable rails, _T. Gorton_,

xxviii, 248.

---- cars, rapidity consistent with safety, xxxv, 197.

----, improved method of constructing, xxxv, 318.

----, cast iron sleepers for, xxxv, 318.

----, resistance of air to trains of, xxxviii, 136.

----, atmospheric, xlix, 228.

---- tunnel, in Pennsylvania, xxix, 73.

Railways, vibration of, _Denham_, xxx, 382.

Railway iron, remarks on, _D. Mushet_, xxxiv, 15.

Rain, amount of, at different heights in the atmosphere, xxix, 354.

----, ----, in S. W. of Ireland, _T. Knox_, xlvi, 394.

----, ----, in the Ghâts of Western India, xxxviii, 103.

----, mean annual amount of, at Perth, Scotland, xl, 342.

----, excessive at Genoa and elsewhere, _J. D. Forbes_, xl, 326.

---- at Paris, in 1823, ix, 194.

----, register of, at Hudson, Ohio, _E. Loomis_, xli, 328; xlix, 282.

----, ----, at Montreal, 1836-1840, _J. S. McCord_, xli, 331.

---- at Westchester, Penn., amount for several years, _W. Darlington_,

vi, 326.

---- ----, register for ten years, xiv, 29.

----, at New Fane, Vt., 1823, '24, _M. Field_, viii, 306.

----, tropical, iv, 375.

----, season of, in Columbia, South America, _R. Wright_, xxxvii, 2.

---- from a clear sky, instances of, xxxvi, 178.

----, _Rowall's_ theory of, xli, 40.

----, remarks on, _W. C. Redfield_, xxxiii, 54.

----, red, i, 309.

----, ----, in Tennessee, _G. Troost_, xli, 403.

----, ----, ----, a hoax, xliv, 216.

---- of mollusca, xxx, 187.

---- of fish, xli, 40.

---- of grain, xli, 40.

---- water, contents of, xv, 181, 185.

----, see farther under _Meteorology_.

Rain-gauge, improved, _G. Chilton_, vii, 326.^f

----, conical, _S. De Witt_, xxii, 321.^f

----, used in New York state, xxv, 267.^f

----, globular, of _Robinson_, xlii, 159.

----, _A. D. Bache_, on the effect of deflected currents of air on the

results with, xxxv, 287.

Rain-marks in sandstone, _W. Buckland_, xxxv, 308.

----, at Storeton Hill, _Cunningham_, xxxvii, 371.

---- in the new red sandstone of New Jersey, _W. C. Redfield_,

xliii, 172; xliv, 136; xlv, 315.

---- in the rocks of the Connecticut valley, _C. Lyell_, xlv, 394.

---- in the Connecticut valley sandstone, _J. Deane_, xlix, 213.

---- in the Potsdam sandstone, _E. Emmons_, xlv, 316.

Rainbow, different brilliancy of the primary and secondary, xxi, 379.

----, supernumerary, _A. C. Twining_, xxxii, 227.

----, accompanied with five supplementary bows, _D. Brewster_, xl, 344.

----, an acoustic, xxi, 381.

_Rainey, P._, on the dry-rot, xxxiv, 169.

Raining trees, notice of, xv, 170.

_Rains, G. W._, on the generation of statical electricity by the

electrical machine, xlix, 93.^f

Raleigh's tyfoon of 1835, xxxv, 210; xxxvi, 59.

Ram, hydraulic, iii, 381.

Rambles of a naturalist, xxv, 425.

_Ramond_, on the vegetation of the Pyrenees, xiv, 377.

Rana, species of, x, 52; xi, 273.

Raphael tapestries, effect of light and air in restoring the colors of,

xxxvii, 214.

Rapids, navigation of, vii, 175.

_Rask_, notice of, iv, 383.

Rat, pouched, of Canada, iv, 183.

----, mode of destroying, xxiv, 205.

Rational expression for sines, tangents and secants, _D. Gould_,

xxii, 392.

Rats, habits of, xlvi, 242.

Rattlesnakes, ii, 229.

----, curious facts respecting the bones of, _J. Green_, iii, 85.

----, disarmed by the leaves of the white ash, _S. Woodruff_,

xxiii, 337.

----, ---- ibid, remarks on, xxx, 208.

----, cure for bite, iv, 61, 189.

----, Turman's snake root in North Carolina considered an antidote for

the bite of, xlii, 43.

----, oil cure for the bite of, xliv, 95.

----, Crotalus durissus, xxiv, 176.

----, habits of, xlvi, 44.

_Rawson_, on fires in London, xxxv, 316.

Ray, solar, see _Light_.

_Ray, John_, some notice of, _C. Fox_, xxxvi, 223.

Razors, paste for, iv, 199.

----, method of sharpening, xxi, 165.

----, effect of cold on, xxvi, 189.

Record of General Science, _R. D. Thomson's_, noticed, xxviii, 365;

xxxii, 212.

Rectification of the ellipse, xviii, 38.^f

Red color in agates, xxxvi, 207.

---- ---- of marshes in the Mediterranean, xli, 193.

---- globules of blood related to Protococcus, xxxvi, 206.

---- rain, i, 309.

---- ---- in Tennessee, xli, 403.

---- ---- ----, a hoax, xliv, 216.

---- snow, x, 192.

---- ----, an animal production, _L. Agassiz_, xli, 64.

---- sulphur spring, Va., xxix, 96.

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