Page:Popular Science Monthly Volume 51.djvu/494

480 amendments to the Federal Constitution, have been placed on terms of full legal right and equality. In no one respect does this antagonism more persistently manifest itself, than in opposition on the part of the white citizen voters to the exercise of free and concurrent suffrage by the negro citizens. Yet, in view of the restraints imposed by the Federal Constitution in respect to political or legal discriminations against the negro race, any change in the way of relief from the situation by State enactment has been regarded as impracticable. A recent constitutional convention of the State of Mississippi seems, however, to have at last most ingeniously solved this difficult political problem, by enacting that every citizen (white or black) of established age shall pay a poll tax, the nonpayment of which shall exclude him from voting; and the collection of the tax out of exempt or non-taxable property—i. e., the possessions mainly of the poorer classes—was also denied. The intent of this provision was therefore manifestly not to raise revenue, but to exclude negroes from voting by reason of nonpayment of the poll tax; and by a like covert purpose the commission of a list of petty crimes which white men do not generally commit, such as thievery, arson, and obtaining money under false pretenses, was also made a disqualification of voting; while robbery, murder, and other robust crimes which are practiced chiefly by white men were not included.

"Within the field of permissible action under the limitations of the Federal Constitution, the Mississippi convention swept the circle of expedients to obstruct the exercise of the franchise for the negro race."—Ratliff vs. Bedle, Mississippi Reports.

the preface to the works of Jean Rey, the philosopher who nearly three hundred years ago first suggested the cause of the increase in weight of lead and tin when burned, M. Edouard Grimaux notices some of the theories that have been put forth on the subject. Boyle explained the increase by supposing that corpuscles of fire, passing through the walls of the vessel in which the calcination took place, became fixed in the metal. This theory was accepted by Stomberg, Lemery, and Nicolas Lefèvre, and was formulated by Lemery: "The pores of the lead are so disposed that the corpuscles of the fire insinuate themselves among them; they remain fastened and agglutinated in the pliant and intricate parts of the metal without being able to escape from them, and add to its weight." Father Chérubin, of Orleans, refuted this explanation by showing that glass was not thus permeable; while Boerhaave, and afterward Boulduc, held that there was no increase of weight in the calcination of metals. Bierne, in 1753, supposed that some rich and sulphurous acid coming from the flame became fixed in the metal. Lavoisier declared the true cause—the fixation in the metal of a part of the air—in 1774, and a little while afterward, in 1775, Bayen called attention in the Journal de Physique to the existence of Jean Rey's Essays.