It is necessary for us to get familiar with some of the protean metamorphoses of matter. Up at New Almaden, above the writer, is a vast mass of porous lava rock into which has been infiltrated a great deal of mercury. How shall we get it out? You can jar out numberless minute globules by hand. This metal, be it remembered, is liquid, and so heavy that solid iron floats in it as cork does in water. Now, to get it out of the rock we apply fire, and the mercury exhales away in the smoke. The real task of scientific painstaking is to get that heavy stuff out of the smoke again. It is changed, volatilized, and it likes that state so well that it is very difficult to persuade it to come back to heaviness again. Take a great mass of marble. It was not always a mountain. It floated invisibly in the sea. Invisible animals took it up, particle by particle, to build a testudo, a traveling house, for themselves. The ephemeral life departing, there was a rain of dead shells to make limestone masses at the bottom of the sea. It will not always remain rock. Air and water disintegrate it once more. Little rootlets seize upon it and it goes coursing in the veins of plants. It becomes fiber to the tree, color to the rose, and fragrance to the violet. But, whether floating invisibly in the water, shell of infusoria in the seas, marble asleep in the Pentelican hills, constituting the sparkle and fizz of soda water, claiming the world's admiration as the Venus de Milo, or giving beauty and meaning to the most fitting symbol that goes between lovers, it is still the same matter. It may be diffused as gas or concentrated as a world, but it is still the same matter.