Impossible to raise hiquids by Suction.

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Chap. 4.]

The divining cups of the Assyrians and Chaldeans appear, from im-perfect accounts of them extant, to have been more artificially contrived.When one was used, it was filled with water, a piece of silver or a jewelhaving certain characters engraved on it was tbrown in; the conjurerthen muttered some words of adjuration, when the demon thus addressed,it is said, “whistled the answer from the bottom of the cup.” These ves-sels were probably so contrived, that the water might compress air con-cealed in some cavity in the base, and force it through the orifice of a mi-aute reed or whistle, as in the musical bottles of Peru . As Julius Cyre-nius says such cups were also used by the Egyptians, it is possible that itwas one of them by which Joseph divined, or affected through policy todivine. Divination by the cup is still practiced in Japan .

It is well known that the jugglers of Asia have always been unri-valled. Even in modern times, some of their tricks are beautiful applica-tions of Science, and are so neatly performed as to baffle the most saga-cious of observers. A full account of them would go far to explain allthe miracles which ancient authors have mentioned, and would afford somecurious Information respecting the secrets of ancient temples.

CHAPTER IY.

Suction: Impossible to raise liquids by that which is so called—Action of the muscles of the thoraxand abdomen in sucking explained—Two kinds of suction—Why the term is continued—Sucking poisonfrom wounds—Cupping and cupping-horns—Ingenuity of a raven—Sucking tubes original atmosphericpumps—The Sanguisuchello—Peruvian mode of taking tea, by sucking it through tubes—Reflections onit.—New application of such tubes suggested—Explanation of an ambiguous proverbial expression.

Air is expelled from such vessels as are figured in the last chapter bythrusting them into a liquid, which entering at the bottom, drives out asit rises the lighter fluid at the top. In the apparatus now to be described,it is withdrawn in a different manner. The vessels are not lowered intowater, but the latter is foreed up into them. The Operation by which thisis accomplished was formerly named suction, from an erroneous idea thatit was effected by some power or faculty of the mouth, independently ofany other influence. A simple experiment will convince any one that thesmallest particle of liquid cannot be so raised:—fill a common flask orsmall bottle within a quarter of an inch of the top of the neck, and placeit in a perpendicular position; then let a person apply his mouth over theorifice, and he may suck forever without tasting the contents; the veriestlover of ardent spirits would die in despair ere he could thus partake ofhis favorite liquor; and the exhausted traveler could never moisten hisparched throat, although the liquid, as in the case of Tantalus, was athis lips.

As remarked in a previous chapter, the error was not exploded tiliTomcelli and Pascal’s experiments proved that water is not raised inpumps by suction, or any kind of attraction, but by pulsion from aerialpressure. Suction therefore, or that which was so called, merely removesan obstacle [air] to a liquid’s ascent—it does not raise it, nor even aid inthe act of raising it. In other words, it is simply that action of the mus-cles of the thorax and abdomen which enlarges the capacity of the lungs

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