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 propelled through the left side of the heart, it is submitted by the agency of the lungs to the air; then taking its true colour, it is transmitted through the arteries to the most remote extremity, and called back again from its life-giving visits, to pass review in its sleepless citadel. Thus the whole volume of blood, which in an adult is from three to four gallons, passes once every three minutes through the heart, on its way to and from the lungs. And those unresting labourers, the heart and lungs, from the first moment of existence, till we return to dust, continue their labours, independent of our volition, wondrous symbols of that Almighty goodness which, whether we wake or sleep, is "new every morning, fresh every moment."

Outlines of the mysterious mechanism of our clay-temple, we ought certainly to study, that we need not through ignorance interfere with those laws on which its organization depends. Rendered precious, by being the shrine of an undying spirit, our ministrations for its well-being, assume an almost fearful importance. Appointed as the mother is, to guard the harmony of its architecture, to study the arts on which its symmetry depends, she is forced to perceive how much the mind is affected by the circumstances of its lodgement, and is incited to cherish the mortal, for the sake of the immortal.