A perfectly safe and pleasant substitute for chloroform, ether, nitrous oxide gas, and all other anaesthetics. Discovered by Dr. U. K. Mayo, April, 1883, and since administered by him and others in over 300,000 cases successfully. The youngest child, the most sensitive lady, and those having heart disease, and lung complaint, inhale this vapor with impunity. It stimulates the circulation of the blood and builds up the tissues. Indorsed by the highest authority in the professions, recommended in midwifery and all cases of nervous prostration. Physicians, surgeons, dentists and private families supplied with this vapor, liquefied, in cylinders of various capacities. It should be administered the same as Nitrous Oxide, but it does not produce headache and nausea as that sometimes does. For further information pamphlets, testimonials, etc., apply to DR. U. K. MAYO, Dentist, 378 Tremont St., Boston, Mass. * * * * * THE OPEN COURT. PUBLISHED BY The Open Court Publishing Company, Rooms 41 and 42, 169-175 LA SALLE STREET, CHICAGO. B. F. UNDERWOOD, SARA A. UNDERWOOD, _Editor and Manager_. _Associate Editor_. The _Open Court_ is a high-class, radical free-thought Journal, devoted to the work of exposing religious superstition, and establishing religion upon the basis of science. It is opposed to all forms of sectarianism, and discusses all subjects of interest in the light of the fullest knowledge and the most matured thought of the age. It has for contributors the leading thinkers and writers of the old and new world. Among those who contribute to its columns are the following writers:--