|
Solar light is a compound substance, consisting of what is termed the seven prismatic colors, namely: red, orange, yellow, green, blue, indigo and violet. These when properly separated comprise the colors of the rainbow, and when combined in a beam, are called white light. A beam of waves from the sun is composed of a bundle of ethereal waves, and these waves are of different lengths. The length of a light-wave is the distance from its crest to a similar point on the next wave. The different lengths of waves produce the different colors to our vision. Those productive of red require 39,000, placed end to end, to make the length of an inch, and those productive of violet require about 57,500. When we contemplate the beauty of the color we call red, as we see it in the rainbow, the solar spectrum, in the red leaves of a blooming rose or elsewhere in nature or in art, let us remember that to produce this color, 477,000,000,000,000 of little ethereal waves enter the eye and impinge on the retina in every second of time; and in the same interval 700,000,000,000,000 of these waves enter our eyes, and produce in us the sensation we call violet. When 577,000,000,000,000 impinge on the retina they produce the sensation of green, and the other colors between the red and the violet are all produced in the same manner. A compound of red and green will produce white light. Yellow and blue will do the same, and for the same reason, because they are complementary colors. No substance which we see in nature or art has any natural color. What we popularly term the color of an object is produced, and its color determined, solely by its power of absorption and reflection, and by these qualities alone. For this we will instance the leaves on a tree, the green grass, the beautiful flowers. A full sunbeam, with all its elements of color, is showered promiscuously on everything in nature, and the molecular construction of this green leaf, for instance, or of the grass, is such that it absorbs all of the ethereal waves except those of a given length, and these it repels or reflects; the reflected waves, twining back and impinging on the retina of the eye, produce in us the sensation of color, and that color is green. All the other waves are absorbed by the leaf, and produce heat instead of light. The beautiful pansy absorbs all the rays of the solar beam except the shortest ones, that are capable of making themselves sensible to our visual organs, and these short waves are turned back by reflection, and, impinging on the retina of the eye, produce in us the sensation of violet; and so it is through all the range of colors. To repeat, every object in the natural world or the world of art receives the full beam of ethereal waves, or its full beam of colors, which are all the colors of the spectrum or rainbow. It then selects such of these waves, as owing to their length and the position of their planes of vibration, it is unable to absorb, reflects them back to the eye, and the length of these reflected waves determines the color of the object. The coloring matter that makes the pigment which to us is black, absorbs all of the solar beam that falls upon it, and hence no color is reflected back to the eye; on the other hand the white paper on which we write absorbs none of these waves, but reflecting the entire beam back to the eye, we have a compound of all of the colors, and this compound is white; hence we call the paper white. As before said, color is not inherent in anything. OCEAN CABLES IN WAR TIME Stretching across the Atlantic bed to-day are twelve cables, ten of them being American and British, two being French, while one German cable has just been completed from the Azores. These cables are as follows: Anglo-American, four cables, from the west of Ireland to Newfoundland; Commercial, three cables, from the west of Ireland to Nova Scotia, but passing Newfoundland in shoal water; direct United States, one cable, from the west of Ireland to Nova Scotia, but passing Newfoundland in shoal water; one French cable, Pougier Quartier, from Brest to St. Pierre, also passing Newfoundland in shoal water; another French cable, Generale, from Brest to Cape Cod; and a German cable, from Emden, via the Azores, to Cape Cod, both passing Newfoundland in shoal water. As the German cable runs partly through Portuguese territory, it is regarded as unreliable and practically valueless to England in time of war. There are two cables from Lisbon to Brazil via the Cape Verde Islands, but their connections are complicated, and they, are deemed unreliable because of the countries in which their terminals lie. No country at war with England would hesitate to strike at her cables, and would cut them, as well as those of the American companies. If the work were to be done by the American Navy, it would not hesitate to cut the cables owned in this country, so as to completely sever England's communications with the western hemisphere. THE FRENCH CABLE FROM BREST. In the case of France, it is pointed out that a warship at sea might pick up the Brest cable (the location of which is known only to the French officials) and could thereby communicate with the home office, learn if war had been declared, and receive precise instructions, repairing the French cable before departing to sever the enemy's wires. The British Navy is supposed to be competent to protect the cables landing at the Cornwall and Connaught coasts, while cable cutting in deep water is only possible to experts on regular slow-going cable ships, whose movements would undoubtedly be watched by Great Britain. Cable experts say that the difficulties met with by the American Navy in cutting cables during the Spanish-American war were the result of inexperience, and that a man who knew his business would, on board a sea-going tug, have all of the Atlantic cables off Cape Canso completely at his mercy, and could finish the job in 48 hours. POINTS OF LAW |