"And here," said the Captain, "let me just cursorily mention one remarkable thing--I mean, that the full, complete correlation of parts which the fluid state makes possible, shows itself distinctly and universally in the globular form. The falling water-drop is round; you yourself spoke of the globules of quicksilver; and a drop of melted lead let fall, if it has time to harden before it reaches the ground, is found at the bottom in the shape of a ball." "Let me try and see," said Charlotte, "whether I can understand where you are bringing me. As everything has a reference to itself, so it must have some relation to others." "And that," interrupted Edward, "will be different according to the natural differences of the things themselves. Sometimes they will meet like friends and old acquaintances; they will come rapidly together, and unite without either having to alter itself at all--as wine mixes with water. Others, again, will remain as strangers side by side, and no amount of mechanical mixing or forcing will succeed in combining them. Oil and water may be shaken up together, and the next moment they are separate again, each by itself." "One can almost fancy," said Charlotte, "that in these simple forms one sees people that one is acquainted with; one has met with just such things in the societies amongst which one has lived; and the strangest likenesses of all with these soulless creatures are in the masses in which men stand divided one against the other, in their classes and professions; the nobility and the third estate, for instance, or soldiers and civilians." "Then again," replied Edward, "as these are united under common laws and customs, so there are intermediate members in our chemical world which will combine elements that are mutually repulsive." "Oil, for instance," said the Captain, "we make combine with water with the help of alkalis----" "Do not go on too fast with your lesson," said Charlotte. "Let me see that I keep step with you. Are we not here arrived among the affinities?" "Exactly," replied the Captain; "we are on the point of apprehending them in all their power and distinctness; such natures as, when they come in contact, at once lay hold of each other, each mutually affecting the other, we speak of as having an affinity one for the other. With the alkalis and acids, for instance, the affinities are strikingly marked. They are of opposite natures; very likely their being of opposite natures is the secret of their inter-relational effect--each reaches out eagerly for its companion, they lay hold of each other, modify each other's character, and form in connection an entirely new substance. There is lime, you remember, which shows the strongest inclination for all sorts of acids--a distinct desire of combining with them. As soon as our chemical chest arrives, we can show you a number of entertaining experiments which will give you a clearer idea than words, and names, and technical expressions."