rapidly than substances having smooth surfaces, are always first and most abundantly covered with dew. In the history of Gideon's fleece, the most striking miracle, as we speak, of the two performed was not that it should be full of water, while all the ground around was dry, but that it alone should be dry, while the surface of the earth around was wet with dew; for a fleece is a good radiator of heat, and would naturally cool before other bodies, and become saturated with dew sooner than many other substances, but unless shaded, all the ground around would be more or less wet with dew, especially in the East, where the dews are much more profuse than in our country. It was consequently a complete reversal of the ordinary laws of nature, that the fleece alone should be dry; and, as if to mark the more special interference of God in this case, it is sufficiently striking that the sacred text with reference to it contains the expression," God did so."

Dew does not in reality present the least chemical difference from pure water. It is, in fact, the purest form in which water is found.* Rainwater is more or less charged with impurities;

* Very minute traces of nitric and muriatic acids have been stated as discoverable in dew occasionally. In hoar-frost, which is frozen dew, none have been found. It is therefore probable such impurities were accidental.

MAGICAL EFFECTS OF DEW.

275

and even the distilled water of the chemist contains them in a very minute degree, but dew may be considered as perfectly pure water, when it forms on a clean surface. Hence its brilliant appearance and the splendid colours it displays at that pleasant time, the charms of which are told in the solemn and beautiful lines of Milton,

"Sacred light began to dawn

In Eden on the humid flowers, that breathed
Their morning incense, when all things that breathe
From earth's great altar send up silent praise

To the Creator, and his nostrils fill

With grateful smell."

Strange properties have been ascribed to it. The ancient alchemists seemed to regard it with a singular veneration, as if it were something more than mere water, and used to employ it in their attempts to dissolve gold. The ladies of antiquity also attributed to dew the magical power of preserving their beauty, and collected it, as we are told, by exposing fleeces to the night air, and wringing them out in the morning. It is not uncommon to hear country people jesting with young people too much attached to their beds, by telling them that if they washed their faces in the morning dew they would never want any other cosmetic. The ancients used to imagine that dew dropped from the stars. How superior to

all these false ideas is the simple and accurate expression of the Scriptures, contained in the beautiful words, "My doctrine shall drop as the rain, my speech shall distil as the dew.”* For if we liken the bedewed surfaces to the " condenser," we see the force and correctness of the expression. The ancients imagined universally that the dew fell, and the same erroneous idea prevailed almost to the end of the last century! Yet for more than three thousand years the true account of its formation, namely, from a vaporous to a condensed state, lay forgotten in the Bible! How satisfactory are such incidental evidences of the Divine origin of the Sacred Word.

If the earth continues to lose heat by radiation, even after the formation of dew, it may be reduced as low as 32°, the freezing point, or even lower. The dew then freezes, its limpid particles become set fast in solid beads and crystals of various forms; thus hoar-frost is produced. The extraordinary beauty of the crystallizations thus formed must have been universally noticed.

There is something eminently interesting in noticing the occasional glimpses of an adjusting principle which we may survey of the kingdom of nature.

* Deut. xxxii. 2.

catch in a

The depo

sition of dew is an illustration in point. The heaviest dews, other circumstances being favourable, succeed the hottest, clearest, and driest days. Hence the dew is most abundant when

it is most necessary. In hot climates the dews are most profuse; and the morning sun rises in its strength upon a landscape which the gentle hand of night has cooled, refreshed, and invigorated with a sea of dew-drops. Thus, though no rain-carrying cloud may cross the blue air during the day, to shed its supplies of refreshing waters upon a parched earth, the clear and brilliant evenings witness, in the phenomenon we have been considering, a grateful and efficient compensation; and the thirsty vegetation, satisfied with its evening potions, is enabled without injury to endure the rays of the burning luminary all the day long.

Dew, in common with all water shed upon the ground, has important duties to fulfil. Besides quenching the thirst of plants, dew is largely instrumental in facilitating the evaporation of some important bodies. Thus, when it is evaporated by the heat of the sun, it is the vehicle by means of which ammonia escapes into the air, and becomes subservient to the wants, not only of the isolated spots in which it was probably first produced, but to those of vegetation at large. Hence, as has been before observed, the farmer's carefully stored heap of manure becomes robbed of half its ammonia, which escapes with the evaporating water, and