সোমবার, ৬ মে, ২০১৩

Communicating with Pheromones

HEAVE-HO: Salvagers planned to use a powerful electromagnet to get at buried treasure, 1913

Image: SCIENTIFIC AMERICAN, VOL. CVIII, NO. 20; MAY 17, 1913

May 1963

Pheromone Messages
?It is conceivable that somewhere on other worlds civilizations exist that communicate entirely by the exchange of chemical substances that are smelled or tasted. Unlikely as this may seem, the theoretical possibility cannot be ruled out. It is not difficult to design, on paper at least, a chemical communication system that can transmit a large amount of information with rather good efficiency. The notion of such a communication system is of course strange because our outlook is shaped so strongly by our own peculiar auditory and visual conventions. This limitation of outlook is found even among students of animal behavior; they have favored species whose communication methods are similar to our own and therefore more accessible to analysis. It is becoming increasingly clear, however, that chemical systems provide the dominant means of communication in many animal species, perhaps even in most. ?Edward O. Wilson?

May 1913

Burning Peat in Germany
?A colossal ?smoke nuisance,? from which the greater part of Europe once suffered more or less, is now rapidly abating with the decline of the time-honored German custom of burning the moors. Moorland, a soil consisting of peat, formed by the partial decomposition of mosses and other vegetation, is in its natural state unfit either for cultivation or grazing. As compared with the modern methods of thorough draining, rolling, mixing with the subsoil, and otherwise permanently reclaiming the moors, the burning process is so wasteful of land that it has generally been given up except in districts remote from settlements.?

Treasure Hunt
?The British frigate ?Lutine? sank in 1799 with ten tons of gold and silver on board. The principal difficulty to be dealt with is presented by the enormous masses of rusted shot and ballast in which the specie is embedded. When operations are renewed early in the coming spring the ?Lyons? will have on board an electric lifting magnet with a lifting capacity of three tons [see illustration]. The masses of metal will be broken up by means of small charges of explosive into pieces small enough for the magnet to deal with.?

Manufacturing Shoes
?Many manufacturers in other industries cannot afford to discard obsolete machines. They have invested too much money in them. Their manufacturing costs are often high because their equipment is out of date. However, every new invention produced by the United Shoe Machinery company means the ?scrapping? of hundreds of machines at the company's expense; in a single year no less than 4,000 machines have been withdrawn to make room for machines embodying the latest improvements. That is why the public is able to buy shoes at a price to meet every purse.?

For a slide show on manufacturing as it used to be, see www.ScientificAmerican.com/may2013/factories

May 1863

Darwin Not an Infidel?
?Of late years men of science and others have wrangled much over Mr. Darwin's work on ?The Origin of Species.? In most of the English and American reviews his treatise has been severely criticized, as having an infidel tendency; not on account of the facts therein given, but the conclusions of the author. He appears to have been very generally misunderstood, judging from the publication of six lectures delivered to workingmen, by Thomas H. Huxley, F.R.S. Broadly stated, the subject of these lectures consists of an inquiry into the origin of species and a discussion on the causes of the phenomena in organic nature. The meaning of organic nature is something that grows, has life and reproductive powers. It is exemplified in the seed of a plant in contradistinction to a grain of sand. Every organism commences existence in an egg cell or seed, and each seed is believed to have been specially created, with special functions and powers of reproduction, as stated in the Scriptures.?

Source: http://rss.sciam.com/click.phdo?i=33b6c75bc64f21c5afc88ce68a1347d6

ben flajnik hunger games premiere red meat bachelor ben jon hamm kim kardashian law school rankings ncaa bracket predictions

কোন মন্তব্য নেই:

একটি মন্তব্য পোস্ট করুন