When the _Vernon_ left Blackwall on her trial trip her engines gave her a speed of about three and a half miles an hour, against a strong wind. Both these vessels, like all the rest of the Indiamen, were full-rigged ships. They were built to be sailing ships with steam auxiliary, and therefore were necessarily very differently constructed from the vessels which were launched about the same time for the North Atlantic trade, such as the _Great Western_, the _President_, and the _British Queen_, all of which were steamers with sail auxiliary. The interdependence of the two means of propulsion must not be lost sight of in considering the naval architecture of the period. The Indiamen of Messrs. Green illustrated the adaptation of steam as an aid to sailing vessels, which even then had not attained their full magnificence and power, but which showed continual improvement in speed as fresh ones were built. This improvement was partly forced upon sailing-ship builders by the opinion, universally held at that time, that steam could never supersede sail for long voyages, owing to the difficulty of carrying enough coal. The steamers designed for the North Atlantic trade, on the other hand, were only intended for a short voyage--short, that is, in comparison with those made by the Indiamen. Consequently, the North Atlantic liners have developed as steamers first and foremost with sail auxiliary, and the latest flyers on this ocean would be of little use as flyers if trading to the Far East or Australia, because they could not carry enough coal and would have to stop frequently to replenish their bunkers, while the liners of the southern and eastern oceans would be equally unable to compete on the North Atlantic routes. Some sailing ships with steam auxiliary were, however, seen on the Atlantic. One of the most remarkable boats of the time was the _Massachusetts_. She arrived at Liverpool after a run of thirty days from New York, which she left on November 17, 1845. She had an Ericsson screw-propeller, which could be lifted when it was desired to run her under sail only. Her screw was merely an auxiliary and was only intended to be of use in calms or against light head winds. She was confessedly an experiment. Her engine-space meant one-tenth less cargo-space, but it was the owner’s idea that, if the voyage were accomplished with so much greater rapidity than the ordinary packet ships could achieve as to recompense them for the loss of tonnage, the experiment would be a success. Her owner was Mr. R. B. Forbes of Boston, and she cost altogether about £16,000. She sailed from Liverpool for New York, beating such well-known sailing ships as the _Shenandoah_ and _Adirondack_ by thirteen days, and the _Henry Clay_ by five days. [Illustration: THE “MASSACHUSETTS.”]