91 (return)
[ The desserts of Syria are characterized, according to Volney (tom. i. p. 351), by woody bushes, numerous rats, gazelles and hares. In the landscape of Patagonia, the guanaco replaces the gazelle, and the agouti the hare.]

92 (return)
[ I noticed that several hours before any one of the condors died, all the lice, with which it was infested, crawled to the outside feathers. I was assured that this always happens.]

93 (return)
[ London's Magazine of Nat. Hist., vol. vii.]

94 (return)
[ From accounts published since our voyage, and more especially from several interesting letters from Capt. Sulivan, R. N., employed on the survey, it appears that we took an exaggerated view of the badness of the climate on these islands. But when I reflect on the almost universal covering of peat, and on the fact of wheat seldom ripening here, I can hardly believe that the climate in summer is so fine and dry as it has lately been represented.]

95 (return)
[ Lesson's Zoology of the Voyage of the Coquille, tom. i. p. 168. All the early voyagers, and especially Bougainville, distinctly state that the wolf-like fox was the only native animal on the island. The distinction of the rabbit as a species, is taken from peculiarities in the fur, from the shape of the head, and from the shortness of the ears. I may here observe that the difference between the Irish and English hare rests upon nearly similar characters, only more strongly marked.]

96 (return)
[ I have reason, however, to suspect that there is a field- mouse. The common European rat and mouse have roamed far from the habitations of the settlers. The common hog has also run wild on one islet; all are of a black colour: the boars are very fierce, and have great trunks.]

97 (return)
[ The "culpeu" is the Canis Magellanicus brought home by Captain King from the Strait of Magellan. It is common in Chile.]

98 (return)
[ Pernety, Voyage aux Isles Malouines, p. 526.]

99 (return)
[ "Nous n'avons pas ete moins saisis d'etonnement a la vue de l'innombrable quantite de pierres de touts grandeurs, bouleversees les unes sur les autres, et cependent rangees, comme si elles avoient ete amoncelees negligemment pour remplir des ravins. On ne se lassoit pas d'admirer les effets prodigieux de la nature."—Pernety, p. 526.]

910 (return)
[ An inhabitant of Mendoza, and hence well capable of judging, assured me that, during the several years he had resided on these islands, he had never felt the slightest shock of an earthquake.]

911 (return)
[ I was surprised to find, on counting the eggs of a large white Doris (this sea-slug was three and a half inches long), how extraordinarily numerous they were. From two to five eggs (each three- thousandths of an inch in diameter) were contained in spherical little case. These were arranged two deep in transverse rows forming a ribbon. The ribbon adhered by its edge to the rock in an oval spire. One which I found, measured nearly twenty inches in length and half in breadth. By counting how many balls were contained in a tenth of an inch in the row, and how many rows in an equal length of the ribbon, on the most moderate computation there were six hundred thousand eggs. Yet this Doris was certainly not very common; although I was often searching under the stones, I saw only seven individuals. No fallacy is more common with naturalists, than that the numbers of an individual species depend on its powers of propagation.]

101 (return)
[ This substance, when dry, is tolerably compact, and of little specific gravity: Professor Ehrenberg has examined it: he states (Konig Akad. der Wissen: Berlin, Feb. 1845) that it is composed of infusoria, including fourteen polygastrica, and four phytolitharia. He says that they are all inhabitants of fresh-water; this is a beautiful example of the results obtainable through Professor Ehrenberg's microscopic researches; for Jemmy Button told me that it is always collected at the bottoms of mountain-brooks. It is, moreover, a striking fact that in the geographical distribution of the infusoria, which are well known to have very wide ranges, that all the species in this substance, although brought from the extreme southern point of Tierra del Fuego, are old, known forms.]

102 (return)
[ One day, off the East coast of Tierra del Fuego, we saw a grand sight in several spermaceti whales jumping upright quite out of the water, with the exception of their tail-fins. As they fell down sideways, they splashed the water high up, and the sound reverberated like a distant broadside.]

103 (return)
[ Captain Sulivan, who, since his voyage in the Beagle, has been employed on the survey of the Falkland Islands, heard from a sealer in (1842?), that when in the western part of the Strait of Magellan, he was astonished by a native woman coming on board, who could talk some English. Without doubt this was Fuega Basket. She lived (I fear the term probably bears a double interpretation) some days on board.]

111 (return)
[ The south-westerly breezes are generally very dry. January 29th, being at anchor under Cape Gregory: a very hard gale from W. by S., clear sky with few cumuli; temperature 57 degs., dew-point 36 degs.,—difference 21 degs. On January 15th, at Port St. Julian: in the morning, light winds with much rain, followed by a very heavy squall with rain,—settled into heavy gale with large cumuli,—cleared up, blowing very strong from S.S.W. Temperature 60 degs., dew-point 42 degs.,—difference 18 degs.]

112 (return)
[ Rengger, Natur. der Saeugethiere von Paraguay. S. 334.]

113 (return)
[ Captain Fitz Roy informs me that in April (our October), the leaves of those trees which grow near the base of the mountains change colour, but not those on the more elevated parts. I remember having read some observations, showing that in England the leaves fall earlier in a warm and fine autumn than in a late and cold one, The change in the colour being here retarded in the more elevated, and therefore colder situations, must be owing to the same general law of vegetation. The trees of Tierra del Fuego during no part of the year entirely shed their leaves.]

114 (return)
[ Described from my specimens and notes by the Rev. J. M. Berkeley, in the Linnean Transactions (vol. xix. p. 37), under the name of Cyttaria Darwinii; the Chilean species is the C. Berteroii. This genus is allied to Bulgaria.]

115 (return)
[ I believe I must except one alpine Haltica, and a single specimen of a Melasoma. Mr. Waterhouse informs me, that of the Harpalidae there are eight or nine species—the forms of the greater number being very peculiar; of Heteromera, four or five species; of Rhyncophora, six or seven; and of the following families one species in each: Staphylinidae, Elateridae, Cebrionidae, Melolonthidae. The species in the other orders are even fewer. In all the orders, the scarcity of the individuals is even more remarkable than that of the species. Most of the Coleoptera have been carefully described by Mr. Waterhouse in the Annals of Nat. Hist.]

116 (return)
[ Its geographical range is remarkably wide; it is found from the extreme southern islets near Cape Horn, as far north on the eastern coast (according to information given me by Mr. Stokes) as lat. 43 degs.,—but on the western coast, as Dr. Hooker tells me, it extends to the R. San Francisco in California, and perhaps even to Kamtschatka. We thus have an immense range in latitude; and as Cook, who must have been well acquainted with the species, found it at Kerguelen Land, no less than 140 degs. in longitude.]

117 (return)
[ Voyages of the Adventure and Beagle, vol. i. p. 363.—It appears that sea-weed grows extremely quick.—Mr. Stephenson found (Wilson's Voyage round Scotland, vol. ii. p. 228) that a rock uncovered only at spring-tides, which had been chiselled smooth in November, on the following May, that is, within six months afterwards, was thickly covered with Fucus digitatus two feet, and F. esculentus six feet, in length.]

118 (return)
[ With regard to Tierra del Fuego, the results are deduced from the observations of Capt. King (Geographical Journal, 1830), and those taken on board the Beagle. For the Falkland Islands, I am indebted to Capt. Sulivan for the mean of the mean temperature (reduced from careful observations at midnight, 8 A.M., noon, and 8 P.M.) of the three hottest months, viz., December, January, and February. The temperature of Dublin is taken from Barton.]

119 (return)
[ Agueros, Descrip. Hist. de la Prov. de Chiloe, 1791, p. 94.]

1110 (return)
[ See the German Translation of this Journal; and for the other facts, Mr. Brown's Appendix to Flinders's Voyage.]

1111 (return)
[ On the Cordillera of central Chile, I believe the snow- line varies exceedingly in height in different summers. I was assured that during one very dry and long summer, all the snow disappeared from Aconcagua, although it attains the prodigious height of 23,000 feet. It is probable that much of the snow at these great heights is evaporated rather than thawed.]

1112 (return)
[ Miers's Chile, vol. i. p. 415. It is said that the sugar-cane grew at Ingenio, lat. 32 to 33 degs., but not in sufficient quantity to make the manufacture profitable. In the valley of Quillota, south of Ingenio, I saw some large date palm trees.]

1113 (return)
[ Bulkeley's and Cummin's Faithful Narrative of the Loss of the Wager. The earthquake happened August 25, 1741.]

1114 (return)
[ Agueros, Desc. Hist. de Chiloe, p. 227.]

1115 (return)
[ Geological Transactions, vol. vi. p. 415.]

1116 (return)
[ I have given details (the first, I believe, published) on this subject in the first edition, and in the Appendix to it. I have there shown that the apparent exceptions to the absence of erratic boulders in certain countries, are due to erroneous observations; several statements there given I have since found confirmed by various authors.]

1117 (return)
[ Geographical Journal, 1830, pp. 65, 66.]

1118 (return)
[ Richardson's Append. to Back's Exped., and Humboldt's Fragm. Asiat., tom. ii. p. 386.]

1119 (return)
[ Messrs. Dease and Simpson, in Geograph. Journ., vol. viii. pp. 218 and 220.]

1120 (return)
[ Cuvier (Ossemens Fossiles, tom. i. p. 151), from Billing's Voyage.]

1121 (return)
[ In the former edition and Appendix, I have given some facts on the transportal of erratic boulders and icebergs in the Atlantic Ocean. This subject has lately been treated excellently by Mr. Hayes, in the Boston Journal (vol. iv. p. 426). The author does not appear aware of a case published by me (Geographical Journal, vol. ix. p. 528) of a gigantic boulder embedded in an iceberg in the Antarctic Ocean, almost certainly one hundred miles distant from any land, and perhaps much more distant. In the Appendix I have discussed at length the probability (at that time hardly thought of) of icebergs, when stranded, grooving and polishing rocks, like glaciers. This is now a very commonly received opinion; and I cannot still avoid the suspicion that it is applicable even to such cases as that of the Jura. Dr. Richardson has assured me that the icebergs off North America push before them pebbles and sand, and leave the submarine rocky flats quite bare; it is hardly possible to doubt that such ledges must be polished and scored in the direction of the set of the prevailing currents. Since writing that Appendix, I have seen in North Wales (London Phil. Mag., vol. xxi. p. 180) the adjoining action of glaciers and floating icebergs.]

121 (return)
[ Caldeleugh, in Philosoph. Transact. for 1836.]

122 (return)
[ Annales des Sciences Naturelles, March, 1833. M. Gay, a zealous and able naturalist, was then occupied in studying every branch of natural history throughout the kingdom of Chile.]

123 (return)
[ Burchess's Travels, vol. ii. p. 45.]

124 (return)
[ It is a remarkable fact, that Molina, though describing in detail all the birds and animals of Chile, never once mentions this genus, the species of which are so common, and so remarkable in their habits. Was he at a loss how to classify them, and did he consequently think that silence was the more prudent course? It is one more instance of the frequency of omissions by authors, on those very subjects where it might have been least expected.]

131 (return)
[ Horticultural Transact., vol. v. p. 249. Mr. Caldeleugh sent home two tubers, which, being well manured, even the first season produced numerous potatoes and an abundance of leaves. See Humboldt's interesting discussion on this plant, which it appears was unknown in Mexico,—in Polit. Essay on New Spain, book iv. chap. ix.]

132 (return)
[ By sweeping with my insect-net, I procured from these situations a considerable number of minute insects, of the family of Staphylinidae, and others allied to Pselaphus, and minute Hymenoptera. But the most characteristic family in number, both of individuals and species, throughout the more open parts of Chiloe and Chonos is that of Telephoridae.]

133 (return)
[ It is said that some rapacious birds bring their prey alive to their nests. If so, in the course of centuries, every now and then, one might escape from the young birds. Some such agency is necessary, to account for the distribution of the smaller gnawing animals on islands not very near each other.]

134 (return)
[ I may mention, as a proof of how great a difference there is between the seasons of the wooded and the open parts of this coast, that on September 20th, in lat. 34 degs., these birds had young ones in the nest, while among the Chonos Islands, three months later in the summer, they were only laying, the difference in latitude between these two places being about 700 miles.]

141 (return)
[ M. Arago in L'Institut, 1839, p. 337. See also Miers's Chile, vol. i. p. 392; also Lyell's Principles of Geology, chap. xv., book ii.]

142 (return)
[ For a full account of the volcanic phenomena which accompanied the earthquake of the 20th, and for the conclusions deducible from them, I must refer to Volume V. of the Geological Transactions.]

151 (return)
[ Scoresby's Arctic Regions, vol. i. p. 122.]

152 (return)
[ I have heard it remarked in Shropshire that the water, when the Severn is flooded from long-continued rain, is much more turbid than when it proceeds from the snow melting in the Welsh mountains. D'Orbigny (tom. i. p. 184), in explaining the cause of the various colours of the rivers in South America, remarks that those with blue or clear water have there source in the Cordillera, where the snow melts.]

153 (return)
[ Dr. Gillies in Journ. of Nat. and Geograph. Science, Aug., 1830. This author gives the heights of the Passes.]

154 (return)
[ This structure in frozen snow was long since observed by Scoresby in the icebergs near Spitzbergen, and, lately, with more care, by Colonel Jackson (Journ. of Geograph. Soc., vol. v. p. 12) on the Neva. Mr. Lyell (Principles, vol. iv. p. 360) has compared the fissures by which the columnar structure seems to be determined, to the joints that traverse nearly all rocks, but which are best seen in the non- stratified masses. I may observe, that in the case of the frozen snow, the columnar structure must be owing to a "metamorphic" action, and not to a process during deposition.]

155 (return)
[ This is merely an illustration of the admirable laws, first laid down by Mr. Lyell, on the geographical distribution of animals, as influenced by geological changes. The whole reasoning, of course, is founded on the assumption of the immutability of species; otherwise the difference in the species in the two regions might be considered as superinduced during a length of time.]

161 (return)
[ Vol. iv. p. 11, and vol. ii. p. 217. For the remarks on Guayaquil, see Silliman's Journ., vol. xxiv. p. 384. For those on Tacna by Mr. Hamilton, see Trans. of British Association, 1840. For those on Coseguina see Mr. Caldcleugh in Phil. Trans., 1835. In the former edition I collected several references on the coincidences between sudden falls in the barometer and earthquakes; and between earthquakes and meteors.]

162 (return)
[ Observa. sobre el Clima de Lima, p. 67.—Azara's Travels, vol. i. p. 381.—Ulloa's Voyage, vol. ii. p. 28.—Burchell's Travels, vol. ii. p. 524.—Webster's Description of the Azores, p. 124.—Voyage a l'Isle de France par un Officer du Roi, tom. i. p. 248.—Description of St. Helena, p. 123.]

163 (return)
[ Temple, in his travels through Upper Peru, or Bolivia, in going from Potosi to Oruro, says, "I saw many Indian villages or dwellings in ruins, up even to the very tops of the mountains, attesting a former population where now all is desolate." He makes similar remarks in another place; but I cannot tell whether this desolation has been caused by a want of population, or by an altered condition of the land.]

164 (return)
[ Edinburgh, Phil. Journ., Jan., 1830, p. 74; and April, 1830, p. 258—also Daubeny on Volcanoes, p. 438; and Bengal Journ., vol. vii. p. 324.]

165 (return)
[ Political Essay on the Kingdom of New Spain, vol. iv. p. 199.]

166 (return)
[ A similar interesting case is recorded in the Madras Medical Quart. Journ., 1839, p. 340. Dr. Ferguson, in his admirable Paper (see 9th vol. of Edinburgh Royal Trans.), shows clearly that the poison is generated in the drying process; and hence that dry hot countries are often the most unhealthy.]

171 (return)
[ The progress of research has shown that some of these birds, which were then thought to be confined to the islands, occur on the American continent. The eminent ornithologist, Mr. Sclater, informs me that this is the case with the Strix punctatissima and Pyrocephalus nanus; and probably with the Otus Galapagoensis and Zenaida Galapagoensis: so that the number of endemic birds is reduced to twenty- three, or probably to twenty-one. Mr. Sclater thinks that one or two of these endemic forms should be ranked rather as varieties than species, which always seemed to me probable.]

172 (return)
[ This is stated by Dr. Gunther (Zoolog. Soc. Jan 24th, 1859) to be a peculiar species, not known to inhabit any other country.]

173 (return)
[ Voyage aux Quatre Iles d'Afrique. With respect to the Sandwich Islands, see Tyerman and Bennett's Journal, vol. i. p. 434. For Mauritius, see Voyage par un Officier, etc., part i. p. 170. There are no frogs in the Canary Islands (Webb et Berthelot, Hist. Nat. des Iles Canaries). I saw none at St. Jago in the Cape de Verds. There are none at St. Helena.]

174 (return)
[ Ann. and Mag. of Nat. Hist., vol. xvi. p. 19.]

175 (return)
[ Voyage in the U. S. ship Essex, vol. i. p. 215.]

176 (return)
[ Linn. Trans., vol. xii. p. 496. The most anomalous fact on this subject which I have met with is the wildness of the small birds in the Arctic parts of North America (as described by Richardson, Fauna Bor., vol. ii. p. 332), where they are said never to be persecuted. This case is the more strange, because it is asserted that some of the same species in their winter-quarters in the United States are tame. There is much, as Dr. Richardson well remarks, utterly inexplicable connected with the different degrees of shyness and care with which birds conceal their nests. How strange it is that the English wood- pigeon, generally so wild a bird, should very frequently rear its young in shrubberies close to houses!]

191 (return)
[ It is remarkable how the same disease is modified in different climates. At the little island of St. Helena the introduction of scarlet fever is dreaded as a plague. In some countries, foreigners and natives are as differently affected by certain contagious disorders as if they had been different animals; of which fact some instances have occurred in Chile; and, according to Humboldt, in Mexico (Polit. Essay, New Spain, vol. iv.).]

192 (return)
[ Narrative of Missionary Enterprise, p. 282.]

193 (return)
[ Captain Beechey (chap. iv., vol. i.) states that the inhabitants of Pitcairn Island are firmly convinced that after the arrival of every ship they suffer cutaneous and other disorders. Captain Beechey attributes this to the change of diet during the time of the visit. Dr. Macculloch (Western Isles, vol. ii. p. 32) says: "It is asserted, that on the arrival of a stranger (at St. Kilda) all the inhabitants, in the common phraseology, catch a cold." Dr. Macculloch considers the whole case, although often previously affirmed, as ludicrous. He adds, however, that "the question was put by us to the inhabitants who unanimously agreed in the story." In Vancouver's Voyage, there is a somewhat similar statement with respect to Otaheite. Dr. Dieffenbach, in a note to his translation of the Journal, states that the same fact is universally believed by the inhabitants of the Chatham Islands, and in parts of New Zealand. It is impossible that such a belief should have become universal in the northern hemisphere, at the Antipodes, and in the Pacific, without some good foundation. Humboldt (Polit. Essay on King of New Spain, vol. iv.) says, that the great epidemics of Panama and Callao are "marked" by the arrival of ships from Chile, because the people from that temperate region, first experience the fatal effects of the torrid zones. I may add, that I have heard it stated in Shropshire, that sheep, which have been imported from vessels, although themselves in a healthy condition, if placed in the same fold with others, frequently produce sickness in the flock.]

194 (return)
[ Travels in Australia, vol. i. p. 154. I must express my obligation to Sir T. Mitchell, for several interesting personal communications on the subject of these great valleys of New South Wales.]

195 (return)
[ I was interested by finding here the hollow conical pitfall of the lion-ant, or some other insect; first a fly fell down the treacherous slope and immediately disappeared; then came a large but unwary ant; its struggles to escape being very violent, those curious little jets of sand, described by Kirby and Spence (Entomol., vol. i. p. 425) as being flirted by the insect's tail, were promptly directed against the expected victim. But the ant enjoyed a better fate than the fly, and escaped the fatal jaws which lay concealed at the base of the conical hollow. This Australian pitfall was only about half the size of that made by the European lion-ant.]

196 (return)
[ Physical Description of New South Wales and Van Diemen's Land, p. 354.]

201 (return)
[ These Plants are described in the Annals of Nat. Hist., vol. i., 1838, p. 337.]

202 (return)
[ Holman's Travels, vol. iv. p. 378.]

203 (return)
[ Kotzebue's First Voyage, vol. iii. p. 155.]

204 (return)
[ The thirteen species belong to the following orders:—In the Coleoptera, a minute Elater; Orthoptera, a Gryllus and a Blatta; Hemiptera, one species; Homoptera, two; Neuroptera a Chrysopa; Hymenoptera, two ants; Lepidoptera nocturna, a Diopaea, and a Pterophorus (?); Diptera, two species.]

205 (return)
[ Kotzebue's First Voyage, vol. iii. p. 222.]

206 (return)
[ The large claws or pincers of some of these crabs are most beautifully adapted, when drawn back, to form an operculum to the shell, nearly as perfect as the proper one originally belonging to the molluscous animal. I was assured, and as far as my observations went I found it so, that certain species of the hermit-crab always use certain species of shells.]

207 (return)
[ Some natives carried by Kotzebue to Kamtschatka collected stones to take back to their country.]

208 (return)
[ See Proceedings of Zoological Society, 1832, p. 17.]

209 (return)
[ Tyerman and Bennett. Voyage, etc. vol. ii. p. 33.]

2010 (return)
[ I exclude, of course, some soil which has been imported here in vessels from Malacca and Java, and likewise, some small fragments of pumice, drifted here by the waves. The one block of greenstone, moreover, on the northern island must be excepted.]

2011 (return)
[ These were first read before the Geological Society in May, 1837, and have since been developed in a separate volume on the "Structure and Distribution of Coral Reefs."]

2012 (return)
[ It is remarkable that Mr. Lyell, even in the first edition of his "Principles of Geology," inferred that the amount of subsidence in the Pacific must have exceeded that of elevation, from the area of land being very small relatively to the agents there tending to form it, namely, the growth of coral and volcanic action.]

2013 (return)
[ It has been highly satisfactory to me to find the following passage in a pamphlet by Mr. Couthouy, one of the naturalists in the great Antarctic Expedition of the United States:—"Having personally examined a large number of coral-islands and resided eight months among the volcanic class having shore and partially encircling reefs. I may be permitted to state that my own observations have impressed a conviction of the correctness of the theory of Mr. Darwin."- -The naturalists, however, of this expedition differ with me on some points respecting coral formations.]

211 (return)
[ After the volumes of eloquence which have poured forth on this subject, it is dangerous even to mention the tomb. A modern traveller, in twelve lines, burdens the poor little island with the following titles,—it is a grave, tomb, pyramid, cemetery, sepulchre, catacomb, sarcophagus, minaret, and mausoleum!]

212 (return)
[ It deserves notice, that all the many specimens of this shell found by me in one spot, differ as a marked variety, from another set of specimens procured from a different spot.]

213 (return)
[ Beatson's St. Helena. Introductory chapter, p. 4.]

214 (return)
[ Among these few insects, I was surprised to find a small Aphodius (nov. spec.) and an Oryctes, both extremely numerous under dung. When the island was discovered it certainly possessed no quadruped, excepting perhaps a mouse: it becomes, therefore, a difficult point to ascertain, whether these stercovorous insects have since been imported by accident, or if aborigines, on what food they formerly subsisted. On the banks of the Plata, where, from the vast number of cattle and horses, the fine plains of turf are richly manured, it is vain to seek the many kinds of dung-feeding beetles, which occur so abundantly in Europe. I observed only an Oryctes (the insects of this genus in Europe generally feed on decayed vegetable matter) and two species of Phanaeus, common in such situations. On the opposite side of the Cordillera in Chiloe, another species of Phanaeus is exceedingly abundant, and it buries the dung of the cattle in large earthen balls beneath the ground. There is reason to believe that the genus Phanaeus, before the introduction of cattle, acted as scavengers to man. In Europe, beetles, which find support in the matter which has already contributed towards the life of other and larger animals, are so numerous that there must be considerably more than one hundred different species. Considering this, and observing what a quantity of food of this kind is lost on the plains of La Plata, I imagined I saw an instance where man had disturbed that chain, by which so many animals are linked together in their native country. In Van Diemen's Land, however, I found four species of Onthophagus, two of Aphodius, and one of a third genus, very abundantly under the dung of cows; yet these latter animals had been then introduced only thirty-three years. Previous to that time the kangaroo and some other small animals were the only quadrupeds; and their dung is of a very different quality from that of their successors introduced by man. In England the greater number of stercovorous beetles are confined in their appetites; that is, they do not depend indifferently on any quadruped for the means of subsistence. The change, therefore, in habits which must have taken place in Van Diemen's Land is highly remarkable. I am indebted to the Rev. F. W. Hope, who, I hope, will permit me to call him my master in Entomology, for giving me the names of the foregoing insects.]

215 (return)
[ Monats. der Konig. Akad. d. Wiss. zu Berlin. Vom April, 1845.]

216 (return)
[ I have described this Bar in detail, in the Lond. and Edin. Phil. Mag., vol. xix. (1841), p. 257.]