Definition of "steamer"

Every since the age of six Troy Belknap of New York had embarked for Europe every June on the fastest steamer of one of the most expensive lines. With his family he had descended at the dock from a large noiseless motor, had kissed his father good-bye, turned back to shake hands with the chauffeur (a particular friend), and trotted up the gang-plank behind his mother's maid, [...]

1918, Edith Wharton, chapter I, in The Marne, New York, N.Y.: D[aniel] Appleton and Company, page 1

But of all the dishes ever brought to table, nothing equals that of the "steamer." It is made by mincing the flesh of the kangaroo, and with it some pieces of pork or bacon. The animal has not any fat, or scarcely any, in its best season; when the meat is chopped up, it is thrown into a saucepan and covered over with the lid, and left to stew or steam gently by the fire-side: it is, from this method of cooking, called "steamer." [...] the flesh soon floats in its own rich gravy: it only requires pepper and salt to render it delicious. No one can tell what a steamer is, unless it has been tasted; it indeed affords an excellent repast, and it is surprising that the steamer, preserved in tins, has not yet been exported to England.

1851, Henry [Saxelby] Melville, chapter XII, in The Present State of Australia, including New South Wales, Western Australia, South Australia, Victoria and New Zealand, with Practical Hints on Emigration; to which are Added the Land Regulations, and Description of the Aborigines and Their Habits, London: G. Willis, Great Piazza, Covent Garden, page 311