WHEN Prince Charlie led his army to Derby and back again, the men walked all the way, and it took two months to go and come. Now, if any one wished, be could go to Derby and back again in one day—by rail. But in the days of Prince Charlie, and for long after, there were no railways, and to walk was the only way in which an army could move from place to place.

But as Prince Charlie marched northward, a little boy of ten, with his head full of stories of Bruce and Wallace, watched eagerly for a sight of the gallant Prince, and all his life he remembered the time of 'the forty-five.'

This little boy was called James Watt. He was not very strong, so he had not been sent to school as other little boys are. He spent most of' his time at home with his mother, who taught him to read. And as soon as lie could read, he devoured every book that he could lay hands on. As James could not play about like other boys, his mother gave him paper and pencil, and lie would spend hours amusing himself by drawing. Often too, he would pull his toys to pieces and make them up again into other things. And often he would spend hours seemingly doing nothing.

'I never saw such an idle boy as you are,' said his aunt, one day, as he sat by the fire watching the kettle boil. ''Fake a book, or employ yourself usefully. For the last hour you have not spoken a word, and have done nothing but take off the lid of the kettle and put it on again, or hold a spoon over the steam, watching how it rises from the spout, and catching the drops as they fall.'

But James was not idle. He felt that there was power in the steam, but how to make use of it he did not know, and his childish brain was trying to find out.

When 'Watt grew up, he tried to earn a living by making mathematical instruments—that is rules, compasses, and other things which are required for making very careful measurements. But many people did not buy these things, and Watt did not make much money. So he began to think of making money in other ways, and all his spare time was spent in trying to find out what steam could be made to do. At last he came very near inventing a steam engine which would work and be of some use. Watt became so excited arid interested about it that he neglected his real business, and at last gave it up altogether. He was poor, ill, and in debt, but kind friends helped him and lent him money so that he might go on making his models and experiments. By this time he was married, and he began to be very unhappy because he was so poor and could not give his wife everything to make her comfortable. But she was a brave woman. 'Do not make yourself uneasy,' she said, 'though things should not succeed as you wish. If this engine will not do, something else will. Never despair.'

And Watt did not despair, and after twenty years of work and failure and disappointment, he at last succeeded.

Watt has been called the improver of the steam engine, but he might almost be called the inventor of it. The steam engines which were known before Watt's were clumsy things, and of little use. It was Watt who showed people that steam could be made to hammer iron, cut steel, pump water, drive the weaver's loom and the spinner's wheel, and later, it was people working with Watt's ideas who laid down rails and sent trains to thunder from one end of the kingdom to the other, and ships to sail up and down our rivers and across the far seas, heedless of wind and tide.

There never was a greater conqueror than steam. It changed the face of the whole world, and time and distance took a new meaning. It was the power of steam which brought the lonely Highlands into touch with all the busy life of towns. It gave work to millions of men; it brought comfort and wealth to thousands more; it did more than anything else to break down the boundaries between Englishman and Scotsman, and not only between Englishman and Scotsman, but between Britons and the people of all the world beyond our island shores.

James Watt himself did not dream of all the wonderful things steam would do, but before he died the first steamboat had been launched upon the Clyde. This boat was called the Comet. It was invented by another Scotsman called Henry Bell, and was launched in 1812 A.D., more than a hundred years ago. But even before that, a little pleasure steamboat had been tried on Dalswinton Loch, in Dumfriesshire, when all the country folk came crowding to see the wonderful new sight of a boat driven by 'reek.' Now all day long the hammer echoes along the shores of Clyde, and from there, great battle-ships, or monster floating cities, glide out to carry the thunders of war or the gifts of peace the world over.