In the quarter of a century which elapsed between 1812, when the Comet first began to churn the waters of the Clyde, and 1837, steam navigation progressed steadily and surely. At first, content with plying along rivers and quiet bays, steamers by-and-by ventured out upon the open sea. We owe the regular establishment of deep-sea packets to the courage and enterprise of Mr. David Napier of Glasgow, "who," says Mr. Scott Russell, "has effected more for the improvement of steam navigation than any other man." He was quick to appreciate the capabilities of steam-vessels, and saw that they were fit for something more than mere inland voyages. Before starting one of them upon the open sea, however, he carefully estimated the danger to be encountered and the difficulties to be overcome. He took passage at the worst season of the year in one of the sailing vessels which formerly plied between Glasgow and Belfast, and which often required a week to perform a journey that is now done by steam in a few hours.

Stationing himself on an elevated part of the deck, he kept a close watch on the movements of the vessel, observing the tossing to which she was subjected by the waves, the extent of the dip when she sank into a trough, the height of elevation when lifted on the summit of a wave, and calculating in his mind how all this would tell on the paddle-wheels. Through the roughest of the storm, when the vessel was pitching worst, and the wind blowing at its fiercest, he kept his place on deck, regardless of the drenching spray and the blast that almost carried him off his legs. When at length he had satisfied himself by the observation of his own eyes and inquiries of the captain and crew, that there was nothing in the voyage which a steamer could not encounter, he retired contentedly to his cabin, leaving everybody astonished at his strange curiosity respecting the effect of rough weather on the ship.

Not long after David Napier started the Rob Roy steam-packet between Greenock and Belfast, and afterwards between Dover and Calais. In the course of two or three years more he had established steam communication between Holyhead and Dublin, Liverpool and Greenock, and various other parts. The length of each unbroken passage was then considered the great difficulty; but as steamers got improved both in form and machinery, passages of greater length were successfully accomplished. Steamers traversed in all directions the German Ocean, the Mediterranean, the Baltic, and, in short, all the waters on the eastern side of the Atlantic; and were in use upon all the rivers and lakes of any size in Europe.

At length, in 1836, the startling project was set on foot of superseding the far-famed New York and Liverpool packet ships by a fleet of steam-ships. Before this the Savannah, a steam vessel of 300 tons, had, in 1819, crossed from New York to Liverpool in twenty-six days, partly with sails and partly with steam; and another steam vessel had, in 1825, made the voyage from England to Calcutta; but one swallow does not make a summer, and many learned folks, on both sides of the Atlantic, shook their heads doubtfully at the daring scheme of regular steam communication across 13,000 miles of ocean. The experiment was to be made, however; and on the 4th April 1838, the Sirius, of 700 tons and 320 horse power, sailed from Cork for the far West. Four days after the Great Western followed in her wake from Bristol.

Great was the excitement in New York as the time drew nigh when the Sirius was considered due. For days together the Battery was crowded with anxious watchers, from the first breaking of the cold, grey dawn till night dropped its dark curtain on the scene. At that time a telescope was a thing to be begged, borrowed, or stolen,—to be got, somehow or other, if only for a minute,—and a man who possessed one was to be looked up to, made much of, and, if possible, coaxed out of the loan of it. All day long a hundred telescopes swept the sea. The ocean steamer was the great topic of the hour, and "any appearance of her?" the constant question when two people met. On St. George's day, the 23d April, a dim, dusky speck on the far horizon grew under the eye of the thousands of breathless watchers into a long train of smoke, beneath which, as the hours wore on, appeared the black prow of a huge steam-boat. There she was, long looked for come at last; and with the American colours at the fore, and the flag of Old England rustling at the stern, the Sirius swept into the harbour amidst the cheers of the multitude, the ringing of the city bells, and the firing of salutes. The excitement reached its climax, and the shouting and firing grew deafening, when, some few hours later on the same auspicious day, the Great Western came to anchor alongside of her rival.

Twenty-two years have passed since then, and the marvel of 1838 has become a mere everyday affair. There are some fourteen different lines of steamers, comprising more than fifty vessels, running between the United States and Europe, to say nothing of the magnificent steam fleets of the Peninsular and Oriental, the Royal West India, British and North American, Pacific, Australian, South Western, and other companies.

The employment of iron in the construction of ships, thus securing at once lightness and strength, and the invention of the screw propeller, in 1836, by Mr. J. P. Smith, a farmer at Hendon, by means of which a vessel can combine all the qualities of a first-rate sailing ship with the use of steam power, gave a great impulse to steam navigation, which is still making steady and continuous progress. From one steam vessel in 1812 the number in the kingdom has risen successively to 20 in 1820, 824 in 1840, and over 2000 in 1860. During 1858, 153 steamers were built in the United Kingdom, of which 112 were of iron. It is interesting to observe the advance in size of the steam vessels from their first introduction on the Clyde.

In the interval between 1812 and 1870 the number of steamers in the United Kingdom has increased from one to nearly three thousand; and the ocean-going steamer of 1870 is nearly six times the length of that of 1825, and seventeen times the length of the Comet, while the difference in tonnage is still greater. How Fulton or Bell would open their eyes at the sight of a vast moving city, such as the Big Ship, an eighth of a mile in length, propelled by both paddle-wheels and screw, each worked by four huge engines!