Scots have had a profound influence on American commerce, culture, and history.

John Macleod tells of three whose works helped shape the face of the United States

ANDREW Carnegie was the first great American capitalist. He can also be seen as the father of modern corporate business. Through steel, he became rich. Fabulously rich. Yet this canny Scot gave away millions and millions of dollars, to a host of good causes - endowing libraries, the performing arts, and so on - and at length died, in comfort, having happily disposed of virtually his entire fortune.

Carnegie was born in Dunfermline in 1835. His father, William, was a handloom weaver, and Carnegie's childhood was overcast by the last death-throes of this cottage industry against the burgeoning might of factory production. It was a battle William Carnegie lost. In 1848 the entire family emigrated to America, settling in Pennsylvania. Carnegie grew to manhood in an Allegheny slum. Things were tough. First he was a bobbin-boy in a textile mill, working 12-hour days: he made $1.50 a week.

Later he tended boilers. He roamed about seeking casual work, sleeping rough. Andrew's break came when he won a telegraph messenger's job with Western Union. By 1858 he was its Pittsburgh superintendent. He saved, hard, and put every cent aside to work for him.

''Eureka!'' Carnegie recorded of the day he received his first dividend-cheque; he had invested in telegraph stock. ''Here's the goose that lays the golden eggs.'' So he explored the delights of free enterprise capitalism. He invested in railroads; then oil. At the age of 28 he enjoyed an income of nearly $48,000. Only $2500 was his Western Union salary.

Carnegie was tired of working for other people. He wanted to be his own chief in his own enterprise: the business he chose was steel. Steel - tough, forged, strong light iron - is to us a commonplace. In the 1850s it was a luxury. But, to use one of Carnegie's business mantras: ''Capitalism is about turning luxuries into necessities.''

Steel was set for a boom in the US. Vast new deposits of iron ore had been found around the Great Lakes, and in Pennsylvania: with all the great rivers as waterways, transport was a cinch. Besides, production was becoming cheaper, and industry bosses looked set to make a pile.

Carnegie's genius lay in attention to detail: with cold ambition, he surveyed any enterprise from the ground up, and when he moved into steel the first thing he did was master its science and study the process of manufacture. He quickly grasped that the fundamentals of steelmaking had not been properly understood.

He hired technicians. ''Find out the truth from the experts,'' was another Carnegie maxim. Scientists, mostly German: the first capitalist to rope in learning in the service of business. So Carnegie set himself to make better steel, more quickly and more cheaply than anyone else. And he succeeded, big-time.

He drove British steel imports out of the market. Then, throughout the States, he everywhere sought to replace heavy chunks of iron with light, tight steel. In 1860 the US produced no steel rails: all had to be imported. By 1873, Americans were producing 115,000 tons of steel rail a year. By 1880 America manufactured 1.25 million tons of steel a year. By 1890 she made over 10 million tons. This was Carnegie's triumph.

Carnegie's genius was built on more than steel chemistry. ''Pioneering don't pay,'' he had recorded: the shrewd entrepreneur did not move at once into new business or new technology, but sat aside at first and learned from pioneers' mistakes. He also grasped the importance of unit costs. If you could break down production costs at every stage and process, any weakness or wastage could be rapidly identified; any fault in plant - or man - could be dealt with. So you raised productivity. So you could slash prices.

Carnegie had a near-evangelical view of steel. He saw it as so central to American life that he believed, with much truth, that the cheaper you made steel the cheaper you made everything else become. The 4000 men at one of Carnegie's plants, in Pittsburgh, could make three times as much steel annually as the 15,000 employed by Krupps in Germany. In 1875 steel rails, in the US, cost $160 a ton. By 1898 Carnegie was producing them for $17 a ton. The blessing to the American economy is incalculable.

Carnegie hated speculation, financiers, and credit. ''Put all your good eggs in one basket and watch it grow,'' he said. He ran his empire as a partnership and refused to float a public company. He saw money as power and was not ashamed of the profit motive. In the worst slumps and declines he always had ample money; with cool efficiency, he would then move to buy out lame-ducks, or ailing partners.

He took pride in selecting and promoting able men. His managers had the highest wages in US industry. He adapted neatly to turns of the market. As the railroad explosion ebbed, he spotted skyscrapers, and directed his industry to making girders for them. He toiled and fought ceaselessly to make ever better steel at ever lower prices. ''Capitalism,'' said Carnegie, ''is creative destruction.''

In 1900 the Carnegie Steel Company recorded annual profits in excess of $40m. The next year he sold the lot, to the new US Steel Company, for the unheard of sum of $447m. Andrew Carnegie was the richest man in the world and that in an age when the forms of corporate and personal taxation dominant today did not exist.

Someone called Carnegie ''the greediest little man that God ever created''. But he was more interested in making money than having it, and wrote that no idol was ''more debasing than the worship of money''. He proceeded to give it away by the million.

In 1892 he founded Carnegie Hall for the performing arts. In 1902 he established the Carnegie Institution, for scientific research. There was also the Carnegie Institution for the Advancement of Teaching (1905) and the Carnegie Corporation (1911) which supported assorted worthy programmes.

The libraries are famous: Carnegie financed 2811 of them, free to the public. He bought 7689 church organs (an odd choice for a freethinker: Carnegie had no religious commitment). He had some loopy schemes: he was, for instance, an ardent supporter of spelling reform. In 1919 it was solemnly reported by the splendidly titled Carnegie Endowment for International Peace, in their Manual of The Public Benefactions of Andrew Carnegie, that he had given away $360,695,653.40 on a host of good causes.

He enjoyed the odd treat. Late in life Carnegie took smug pride in acquiring Skibo Castle, in his native Scotland. Quaintly, he decorated his homes in tartan wallpaper. By the time he died, in 1919, he had been awarded the formal freedom of 50 cities across the United States.

Andrew Carnegie. Made in Scotland. From girders.