Palestine is almost or quite the farthest south, in that particular quarter of the globe where the vine is luxuriant. We read, indeed, in the Old Testament, of the vine being used for vintaging purposes in Egypt; and numerous hieroglyphics attest that this was not an exceptional, but a common practice. No doubt, in modern times, the culture of the vine in Egypt is insignificant; yet this is partly due (as in the corresponding case of Palestine, where the artificial growth of the vine has much fallen off) to political causes, to the want of energy of the people, and to the religious objection of most of them to the use of wine. We have already shown that the valley of the Jordan has most probably a climate, at least, as warm as that of northern Egypt; and as this is unquestionably on or near the productive limit of the vine in approaching the equator, so vineyards might be expected to flourish on the mountains of Judæa, but to fail on the plains of Jericho. This, as has been shown, is the testimony which Scripture yields on the subject. It is confirmed by the reports of modern travellers; only it must be recollected that there is now no inducement for urging the production of the grape in districts abandoned to erratic and lawless tribes.

In the more purely scientific view of the question, it is to be observed that the "Equatorial limit" of the growth of plants is far less vigorously defined than the "Arctic limit." This is generally admitted; and the causes of it are sufficiently obvious. The northern limit is usually defined by two circumstances: first, the existence of frosts in winter sufficient to destroy the vitality of the plant; and, secondly, the deficiency of summer heat requisite to ripen the wood of the tree or to bring the fruit to maturity. Towards the equator, the increase of solar heat and the absence (in some countries) of sufficient moisture do not so suddenly produce their effect. And in the case of plants cultivated for human use, like vines, the influence of climate may be warded off by certain precautions as to exposure and the like.* Thus, we are told, that

* On the whole, it is difficult to add much to the facts about the southern limit of the productive vine which are relied on by Schouw-namely, that Von Buch places it in the island of Ferro (Canaries) in lat. 27° 45', with a mean temp. of 71° Fahr. In Barbary the vine succeeds only on the coast. At Cairo, NEW SERIES.-VOL. XV. NO. II.—APRIL 1862.

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the vine may be brought to bear fruit in Egypt, in Southern Persia, and even in Hindostan, by planting it in pits sheltered from the rays of the sun. In most countries, too, there are spots exceptionally cool and moist, where, under proper care, cultivation may be carried on with even more than usual advantage, because the benefits of a fine climate may be obtained without its drawbacks. Of this description, most probably, was the locality of Engeddi, which is believed to have adjoined the western shores of the Dead Sea, and is still marked by a splendid spring which no doubt gave its name to the spot. In one place in Scripture* (2 Chron. xx. 2), Engeddi is characterised as productive in palm trees; and in another (Cant. i. 14), as distinguished by choice vineyards. Had the climate of Palestine in the days of Solomon been hotter than it is now, it is fair to infer that the culture of grapes in this the most southern, the lowest in point of level, therefore the hottest part of Judæa, would have been impossible. Besides, if we may be allowed to draw an inference from the climate of the neighbouring country of Egypt, the importance of grape culture, attested there by the Old Testament writings, and by the numerous and characteristic hieroglyphics which Kitto has transferred to his work on the "Physical Geography of Palestine," leads us to the conclusion that the climate there might be esteemed to have anciently been more adapted to that culture, therefore cooler, certainly not less adapted, that is, hotter, than it is at present.

To sum up the whole, we seem to be entitled to conclude

1. That, judging from the known thermometric conditions of the growth and maturity of the date palm, compared with the evidences in Scripture of its distribution and culture in Ancient Palestine, the mean temperature of the site of Jerusalem, when reduced to the level of the sea, can have then differed but little from 70° Fahrenheit, which is its present value according to the best authorities. We conclude, with

with a mean temp. of 72°, the culture is insignificant. These facts point to the coincidence of the southern limit of the vine with the isothermal line of 72° which we have seen to pass a little to the south of Palestine.

* Hazazan Tamar signifies "felling of palm trees." Comp. Ecclesiasticus, xxiv. 14, "I was exalted as a palm tree in Engaddi."

still more certainty, that the temperature could not anciently have been colder than this.

2. That, comparing the conditions which limit the cultivation of the vine, we find that as it certainly was not anciently less, but more general and advantageous than at present, the climate of Palestine could not have been materially hotter than that which now belongs to its geographical position, taking also into account the modifying influence of height above the sea-level.

3. That this argument is enhanced by the evidence from hieroglyphics, and also from Scripture, that the cultivation of the grape was anciently more extensive in Egypt than it is now. That while this might be seen to point to the conclusion that these countries are hotter now than formerly, the difference is sufficiently accounted for by political circumstances, and the conclusion is itself negatived by the evidence to the contrary derived from the date palm.

4. Hence the climate of Palestine, being neither sensibly hotter nor colder than it anciently was, is, of course, unchanged; and the direct evidence of modern travellers on the distribution of the vine and palm in that country, leads to the same result.

TABLE I.-Mean Temperatures referred to in preceding Paper.

First limit: Palm in full fruit-TUNIS,
Second limit: Palm in flower-ALGIERS, PALERMO,
Third or extreme limit of growth-NICE, ROME,

Mean Temp.

Does Magnetism possess any Influence over Organic Forces ? By H. F. BAXTER, Esq.*

The most inattentive observer of natural phenomena would soon be led to infer, that between the variations of the seasons and the development of organised bodies, whether plants or animals, a most intimate relation and connection existed; that between heat and light on the one hand, and vegetation on the other, the connection would be found, upon the least reflection, to be so intimate and dependent that the former might be considered, in ordinary language, as the cause of the latter. No special observation, by means of experiment, would be requisite to confirm this conclusion. It is far otherwise, however, with regard to phenomena in which no periodicity or variation during their occurrence is observed; influences may exist, and be producing powerful effects, and yet, from their constant action, be entirely overlooked,―here, it need not be remarked, we require specific observation for their elimination. Now, since the discovery of diamagnetism, and the fundamental fact that all substances whatever are subject to magnetic influence, the conclusion that terrestrial magnetism must exercise some most important part over natural phenomena is irresistibly forced upon our minds. To solve one of the questions which naturally arise from this conclusion was the object of the present investigation; and although the results were negative, from the inadequacy of the means employed, the principles upon which the experiments were conducted may perhaps be of some value, and worthy of publication; but a minute detail of the experiments themselves may not be necessary, and will therefore be omitted.

Becquerel,† in some experiments upon the influence of electricity over the circulation of the sap in the Chara, placed a stem of the plant in a helix traversed by a current of electricity, so that the convolutions should be either parallel or perpendicular to the motion of the sap; but no influence appeared to be exerted over the circulation of the fluid.

* Read before the Edinburgh Botanical Society, March 13, 1862.
† Traité de l'Electricité, t. vii. p. 250.

Dutrochet submitted a plant (Chara) for ten minutes to the influence of a powerful electro-magnet (which could support about a couple of tons weight), without any effect being observed upon the motion of the fluid.

Wartmannt says, "that one of the principal objects of his observations has been that of the influence of electro-magnetic induction on the circulation of the sap and the direction of the organs;" but has not, so far as I am aware, published his experiments or the results.

The experiments of which the following are the results were undertaken during the years 1852, 1853, 1854, and 1855; and it was during this inquiry that the question arose as to "the influence of magnetism over chemical action," which formed the subject of two papers that have already appeared in this Journal; and in these papers will be found described the magnet and electro-magnet that were employed on the present occasion. Although the results of the experiments recorded in the present paper were, for. the most part, obtained prior to that inquiry, they may nevertheless form a natural sequel to it. Their publication has been delayed from a hope that some more positive results might, on further investigation, be obtained; but the want of the necessary means, and the expense attending the prosecution of the experiments, were such that the inquiry has, for the present, been reluctantly abandoned.

As it may be considered a law in vegetable physiology that all plants have a tendency, during the germination of the seeds, to develope in two diametrically opposite directions (the root and the stem), the question arose, might not this direction be altered or counteracted by submitting the seeds whilst germinating to the influence of magnetic force? The experiments will be arranged under two heads: First, those in which the line of magnetic force was directed perpendicularly to the seed; and, secondly, those in which the line of force was directed transversely to the seed.

* Comptes Rendus, t. xxii. p. 621 (1846).

† Philosophical Magazine, 1851, p. 378.

Edin. New Phil. Jour., New Series, vol. v. p. 235; vol. vi. p. 25.