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No one can draw any clear distinction between individual differences and slight varieties; or between more plainly marked varieties and subspecies, and species.

why should we doubt that variations in any way useful to beings, under their excessively complex relations of life, would be preserved, accumulated, and inherited?

The theory of natural selection, even if we looked no further than this, seems to me to be in itself probable. I have already recapitulated, as fairly as I could, the opposed difficulties and objections: now let us turn to the special facts and arguments in favour of the theory.

On the view that species are only strongly marked and permanent varieties, and that each species first existed as a variety, we can see why it is that no line of demarcation can be drawn between species, commonly supposed to have been produced by special acts of creation, and varieties which are acknowledged to have been produced by secondary laws. On this same view we can understand how it is that in each region where many species of a genus have been produced, and where they now flourish, these same species should present many varieties; for where the manufactory of species has been active, we might expect, as a general rule, to find it still in action; and this is the case if varieties be incipient species.

preserve the most divergent offspring

Hence during a long-continued course of modification, the slight differences, characteristic of varieties of the same species, tend to be augmented into the greater differences characteristic of species of the same genus.

New and improved varieties will inevitably supplant and exterminate the older, less improved and intermediate varieties; and thus species are rendered to a large extent defined and distinct objects.

This grand fact of the grouping of all organic beings seems to me utterly inexplicable on the theory of creation.

But why this should be a law of nature if each species has been independently created, no man can explain.

As natural selection acts solely by accumulating slight, successive, favourable variations, it can produce no great or sudden modification; it can act only by very short and slow steps

The wonder indeed is, on the theory of natural selection, that more cases of the want of absolute perfection have not been observed.

As natural selection acts by competition, it adapts the inhabitants of each country only in relation to the degree of perfection of their associates;

we believ

His Communist Manifesto is nothing more than a rant about the evils of this group and how they have inflicted harm and damage to everyone around them through colonialism and ingenuity.

se bailouts are transfers of wealth -- not from the rich to the poor, but from the working middle class to both the upper and lower classes.

True: all the

1925-1926   Introduction of lightweight, air-cooled radial engines The introduction of a new generation of lightweight, air-cooled radial engines revolutionizes aeronautics, making bigger, faster planes possible.

  1917   The Junkers J4, an all-metal airplane, introduced Hugo Junkers, a German professor of mechanics introduces the Junkers J4, an all-metal airplane built largely of a relatively lightweight aluminum alloy called duralumin.

1904   Concept of a fixed "boundary layer" described in paper by Ludwig Prandtl German professor Ludwig Prandtl presents one of the most important papers in the history of aerodynamics, an eight-page document describing the concept of a fixed "boundary layer," the molecular layer of air on the surface of an aircraft wing. Over the next 20 years Prandtl and his graduate students pioneer theoretical aerodynamics.

1933   First modern commercial airliner In February, Boeing introduces the 247, a twin-engine 10-passenger monoplane that is the first modern commercial airliner. With variable-pitch propellers, it has an economical cruising speed and excellent takeoff. Retractable landing gear reduces drag during flight.

935   First practical radar British scientist Sir Robert Watson-Watt patents the first practical radar (for radio detection and ranging) system for meteorological applications. During World War II radar is successfully used in Great Britain to detect incoming aircraft and provide information to intercept bombers.

1937   Jet engines designed Jet engines designed independently by Britain’s Frank Whittle and Germany’s Hans von Ohain make their first test runs. (Seven years earlier, Whittle, a young Royal Air Force officer, filed a patent for a gas turbine engine to power an aircraft, but the Royal Air Ministry was not interested in developing the idea at the time. Meanwhile, German doctoral student Von Ohain was developing his own design.) Two years later, on August 27, the first jet aircraft, the Heinkel HE 178, takes off, powered by von Ohain’s HE S-3 engine.

  1939   First practical singlerotor helicopters Russian emigre Igor Sikorsky develops the VS-300 helicopter for the U.S. Army, one of the first practical singlerotor helicopters.