AND OF THE PHYSICAL SCIENCES. 



■Worms in the Eyes of the Perch. — Dr Nordmann discovered parasitic worms 

 in the eyes of several distinct species of the perch. These eye- worms were sometimes 

 in such numbers as must have interfered with that distinct sight of passing objects, 

 which appears necessary to enable predaceous animals to discover their prey, in time 

 to dart upon and secure it; in a single eye the Doctor detected, in different parts, 

 360 of these minute animals ! VThen numerous, they often produce cataracts in the 

 eye of the fishes they infest. The little animals which he found appear something 

 related to the Planaria, or pseudo-leech; and, to judge from Dr Nordmann's figures, 

 seem able, like it, to change its form. Underneath the body, at the anterior extre- 

 mity, is the mouth ; and in the middle are w^hat he denominates two sucking cups ; 

 these are prominent, and, viewed laterally, form a truncated cone ; the anterior one is 

 the smallest and least prominent, and more properly a sucker; the other, probably, 

 has other functions, since he could never ascertain that it was used for prehension. A 

 kind of metamorphosis seems to take place in these anim.als, for our author observed 

 that they appeared under three different forms. These Uttle pests, small as they are, 

 have a parasite of their own to avenge the cause of the perch, for Dr Nordmann ob- 

 served some very minute bro\vn dots, or capsules, attached to the intestinal canal, 

 which when extracted, by means of a scalpel formed of the thorns of the creeping 

 cereus, and laid upon a piece of talc, the membrane that enclosed them bm-st, and forth 

 issued living animalcules, belonging to the genus Monas, and smaller than Monas 

 ntomus, which immediately turned round upon their own axes with great velocity, and 

 then jumped a certain distance in a straight line, when they again revolved, and again 

 took a second leap. Looking over our author's list of eye-worms that infest fishes, 

 we find that five out of seven are attached to different species of perch, and one can- 

 not help feehng some commiseration for these poor animals ; but, when we recollect 

 that they form the most numerous body of predaceous fishes in our rivers, we may 

 conjecture that thus their organs of vision are rendered less acute, and that thus thou- 

 sands of roach, dace, carp, and tench, may escape destruction — Kirhtj's Dridgewater 

 Treatise, 



BOTANY AND HORTICULTURE. 



Fountain Tree. — There are few rivulets, and only three springs, in the Island of 

 Ferro, one of the Canaries ; and these are on a part of the beach \vhich is nearly 

 inaccessible. To supply the place of fountains, however, Nature bestowed upon this 

 island a species of tree, supposed to be nearly allied to the Laurus Iiidica, possessing pro- 

 perties unknown to trees in all other parts of the world. These fountain trees were of 

 moderate size, and their leaves were straight, long, and evergreen. Around the summit 

 a small cloud perpetually rested, which so drenched the leaves with moisture, that they 

 constantly distilled upon the ground a stream of fine clear water. To these trees, as 

 to perennial springs, the inhabitants of Ferro resorted, and were thus supplied with a 

 sufficient abundance of water for themselves and for their cattle. The last of these 

 remarkable productions received the appellation of the Holy Tree, and it is said to 

 have been destroyed by a dreadful hurricane in 1612. Its real existence has been 

 completely established in the Viacjcro Universal di P. Estala, tome xi, ; but by 

 this account the water was merely condensed upon the leaves. Purchas, in his 

 " Book of Pilgrimages, 1639," states that he had been told by Mr Lcv.is Jackson, 

 of Holborn, London, who visited Ferro in 1G18, that the fountain tree he had 

 seen was as large as a middling-sized oak, six or seven yards high, with a white bark, 

 like that of hardbeam; its leaves were like that of the bay, white underneath and 

 green above. Parkinson, in his ** Theatrura Botanicum," published at London in 

 1H40, also mentions this tree. He says that the islanders called it Garoe, the Spa- 

 niards Arhor sancti; and that the ancient historians call it Til; and adds, "It is 

 thought that Solinus, and Pliny in his Lib. 6, c. 32, meant this island, under the 

 name of Onibrion and Pluvialis: for he there saith, that in the island Ombrion grow 

 trees hke unto Ferula, from whence water is wTung out; from the black ones cometh 

 bitter water, and from the white that which is sweet and pleasant to drink." 



Great PRor)UcTivE>"Ess ot' the Orange Trees or St Michaels. — The St 

 Michael oranges have long been celebrated for their delicious flavcur, and the 

 abundance and sweetness of their juice; when allowed to ripen before being pulled, 

 they are inferior to none in the world. On the other hand, the lemons of that island 

 are less esteemed than those of vai-ious other countr.cs, on account of the small quan- 

 tity of juice in them; and therefore they arc not much in demand. The orange and 

 lemon trees blossom in February and March. At this season, nothing can be more 

 gratifying to the sight than the appearance presented by these trees; the glassy green 

 of the old leaves, the light fresh tints of those just shooting forth, the brilliant yellow 

 of the ripe fi'uit, and the delicate purple and white of the flower, form a delightful 

 contrast. Both orange and lemon trees are from fifteen to twenty feet in height, 

 and their common annual produce is from GOOD to 8000. Dr Webster mentions, 

 that he has known, in a very abundant year, 26,000 oranges to be obtained from one 

 tree, and 29,000 from another. These, however, are the greatest quantities v.hich 

 have ever been knowTi to be gathered from a single tree in a year. 



New Method of Blanching Celery. — In the March number of the Iriah 

 Farmer s and Gardener s Magazine, a Mr Coglan recommends the following me- 

 thod of cultivating celery, by which he states he has been successful for many years 

 in preserving this favourite vegetable from what is called "rust," occasioned by the 

 attack of grubs. In the month of October he plants the ground, designed for celery 

 the ensuing year, with early York cabbage, which will be cleared away by the first 

 week in June, the most proper season for planting. Previous to forming the drills, 

 he collects the stalks and remaining leaves of the cabbages, and places them in small 

 heaps on the bed. After lying a day or two, they will be found to have collected a 

 great number of slugs and other vermin, which may be easily destroyed. The ground 

 is then prepared and the plants put in; when ready for blanching, the loose leaves 

 of each plant are tied up, and strong wheaten straw laid full length along the side of 

 the drills, and staked down so much that it will completely exclude the light (except- 

 ing at the top, which is all that is requisite). By this treatment, he says, in the 

 course of a month he has gathered celery perfectly free from either rust, grub, or in- 

 sect. 



MINERALOGY. 



CHEMICAL COMPOSITION OF NATIVE GOLD. 



We principally confine our remarks on the chemical composition of native gold, to 

 that found in the Uralian mountains. 



Gold being a simple substance, is of course unsusceptible of decomposition; but, 

 like most other simple bodies, it is never found in the earth in a state of purity, being 

 always more or less combined with silver. 



Although the mines of Colombia have long been celebrated for the quantity of gold 

 found in them, yet it has recently been ascertained that the native ore of that country 

 contains a smaller proportion of gold than that of most others. According to the expe- 

 riments of BoussingauU, who analyzed gold from different places in Colombia, he found 

 it combined with silver in variable quantities, but invariably in definite proportions, 

 namely, one atom of silver with 2, 3, 4, 5, 6, 8, and 12 atoms of gold. We are in- 

 formed by Fordyce, that he examined gold from Konsberg in Norway, and found it to 

 consist of 28 pai'ts gold, and 72 of silver, in the 100 parts. Klaproth, in analyzing 

 gold from Schlangenberg in the Altai, found that it contained 64 parts gold, and 36 

 of silver; and Lampadius found in gold ore, whose locality was unknovm to him, 96.6 

 parts of gold, and the remainder consisted of silver and iron. Mr G. Rose, who ac- 

 companied Baron Humboldt into Siberia, made a collection of gold ores, for the ex- 

 press purpose of testing the position assumed by the French chemists. 



Gold ore is found in the Uralian mountains in rocks, and also scattered amongst 

 sand ; in which last situation it is now almost entirely sought after, being much less 

 laborious than extracting it from rock veins. Its tUscovery in this situation occurred 

 in 1819, since which period rock mines have been abandoned. 



The gold which is procured in rocks is universally found in quartz. At Beresow, 

 it occurs in a crystallized form ; at Newiansk, in plates ; but at Czarewo Alexander- 

 owsk, masses are met with which weigh from 18 to 96 lbs. troy. 



The proportions of gold and silver from the different localities vary considerably. 

 The following are the extreme limits of this variation: — 



SILVER. GOLD. 



Hiel rock 87.40 12.60 



Schaitansk 95.10 4.90 



The follomng important consequences were deduced by Rose from his analysis. He 

 remai'ked that gold and platinum were never fomid associated. 



1. Gold ore does not contain gold and silver in definite proportions. 



2. From the above fact, he infers that gold and silver are isomorphous. 



3. Native gold always contains silver, copper, or iron. The smallest quantity of sil- 



ver in combination, was in a specimen from Schabrouski, which only contained 

 16 per cent, of silver, while 35 per cent, of copper was found. 



4. The specific gravity is in the inverse ratio of the proportion of silver contained 



in the ore. Gold obtained by fusion has a greater density than in a native 

 state; but this may arise from cavities contained in the latter. 



5. He found a difference in composition in specimens from the same locality. 

 G. Gold found in veins varies in different parts of the same mine. 



7. Gold from sand contains more silver than that found in veins; that from sand 

 being 89.7 per cent, of silver, and from veins, 79.1. — Foffgendorff, Ann. 

 xxviii., 566. 



EniDLE Rocks. — Near the Ural mountains in Siberia, a substance called " rock 

 meal" — powdered gypsum — is found, which the natives mix with their bread, and eat. 

 The Tartars likewise eat the hthomarge, or rock marrow; and use rock butter as a 

 remedy for certain disorders. 



GEOLOGY AND PHYSICAL GEOGRAPHY. 



Threatened Eruption of Vesuvius. — According to late accounts from Naples, 

 VcsmnuB continued to throw out stones and cinders, and a grand eruption was expect- 

 ed. Some slight shocks of an earthquake were lately felt in the south of Italy. 



Water of the Seine. — It was not thought that the basin of the Seine — 1 mean 

 all that portion of ground in Franco watered by streams, great or small, which flow 

 into that river — annually received in rain a quantity of water equal to the tribute car- 

 ried by the Seine to the sea in the same spicc of time. Perraul and INIariotte were 

 tlie first who studied tlie question, supported by experiments, and found, as is common 

 in similar cases, that the vague ideas of their predecessors were the very contrai-y of 

 the truth. According to Mai-iotte, the Seine discharges every year into the sea only 

 a sixth of the quantity of rrater which falls in all the extent of its basin, in rain, snow, 

 and dew. The other five-sixths must either be e''aporated to form clouds, absorbed 

 by the superficial earths in which plants find nourishment, or penetrate, by fissures in 

 rocks, into the internal reservoirs from which fountains issue. Mariottc's calculation 

 has been re-made on data more exact, especially as regai-ds the gauging of the Seine. 

 The following are the results, as they were stated in an excellent memoir, hitherto 

 impublishod, by Mr Dausse, civil engineer: — *'The basin of the Seine has an area, 

 4,327,000 hectors. Were the water falling into this basin not to evaporate, nor 

 penetrate into the soil, and were the ground every where horizontal, it would form at 

 the end of the year a liquid sheet of 53 centimetres (20 inches) deep. It is easy to 

 see that such a sheet would contain a volume of 22,933 millions of cubic metres of water. 

 Now, at the Bridge of the Revolution, the mean proportion of the water passing there 

 is at the rate of 255 cubic metres in a second, or 22 millions of cubic metres in a day, 

 or 8042 millions of ditto in a year. This last number is to 22,933 millions of cubic 

 metres, whiclx is the annual amount of the rain received by the basin of the river, as 

 100 is to 285, or almost as 1 to 3. Thus, the volume of water passing annually under 

 the Paris bridges is scarcely the third of that which falls in rain into the basin of the 

 Seine. Two-thirds of this rain either return to the atmosphere, by means of evapora- 

 tion, or sustidn vegetation and the life of animals, or run into the sea by subterranean 

 communications." — Literary Gazette, 20tk June, 



