If a child is found to have been starved to death in a cellar or an attic, a cry of horror is raised over it. If two or three wandering boys, as it happened the other day at Lowell, come upon some noxious roots, and, in obedience to their omnivorous instinct, devour them, and pay the forfeit, the whole country hears of it. If a family or two get hold of some ill-conditioned meat, and suffer for it, the groans of their colics are echoed all over the land. If a milkman misrepresents his honest cows by falsifying their product, the chemist detects him, and the press puts him in the pillory. If the Cochituate or Mystic water is too much like an obsolete chowder, up go all noses, and out come all manner of newspaper paragraphs from "Senex," "Tax-payer," and the rest. But air-poisoning kills a hundred where food-poisoning kills one. Let me relate a circumstance which happened in Ireland, to which circumstance, in all probability, I owe the pleasure of being listened to at this moment by some among our hard-working, adopted citizens who are before me. When I say to you, meaning to speak the words of sober truth, that a single physician, by a single and simple measure, saved more lives than were lost at Waterloo by the British army and all its allies, leaving out the Prussians, you will suspect me of exaggeration, not very uncommon in public speakers. I will therefore intrench myself behind certain details which I have often before cited, but not in the presence of a gathering of this kind. Dr. ROBERT COLLINS was Master, as it is called, of the great Dublin Lying-in Hospital, where the annual rate of births was between two and three thousand, from the year 1826 to 1833. A work of his, containing the results of his practice during his seven years of service, was published in Boston in 1841, by order of the Massachusetts Medical Society, for the use of its members. I consider him vouched for as authority, therefore, by men in whom you can put confidence. Dr. COLLINS makes the following statement:-- When his predecessor, Dr. JOSEPH CLARKE, was in office, in the year 1784, he found that seventeen children in the hundred, nearly one in six, died within the first fortnight after birth, nineteen-twentieths of these of one particular disease peculiar to very early infancy. Looking for the cause of this frightful mortality, he thought he found it in a foul and vitiated state of the air of the hospital. So he had some openings of considerable size made in the ceiling of each ward, and three holes, of an inch in diameter, through each window at top: the doors, too, were perforated with numerous holes. In this way, a free circulation was secured, and so arranged, that the nurses could not control it; for some of the old-fashioned nurses would not have opened a window in the Black Hole at Calcutta, for fear the inmates should catch a cold.