[ Martin's Sportman's Almanack, Kalendar, and Travelers' Guide for 1818 ]
I've not been able to find any information about this publication; the introduction to this volume strongly implies 1818 was the first year of publication, and there was another issue for 1819, but that may have been it. Perhaps the best explanation of this work's purpose is to be found in its full title: Martin's Sportman's Almanack, Kalendar, and Travelers' Guide for 1818; Containing Ample Directions, in Monthly Order, for Shooting, Coursing, Hunting, and Fishing, in all its varieties, after the most approved Systems, matured by Experience: The Almanack of the Year; Correct Tables of Whatever is Useful as a Kalendar; A Series of Maps for Every County in England, etc. etc. The Whole Adapated as a Manual for the Sportsman and Country Gentleman. Published in London by Simpkin & Marshall.
And no, "Sportman's" is not a typo, but the actual title of the magazine as it was printed.
The almanac contains the following brief entry on Newfoundland dogs, and is notable for its reference to there being several "species" of Newfoundland dogs — surely one of many indications, from the early 19th Century, that strict codification of breeds was still some years in the future.
Sportsmen frequently take a Newfoundland dog with them, when shooting at any species of game; those dogs are not to be excelled for fineness of nose, or sagacity; mild, and tractable, with kind treatment; savage, and fierce, when ill treated. A Newfoundland dog very soon comprehends you, and will diligently attend to you, never leaving your heels until commanded; put him on the scent of a wounded head of game, and he will hunt up to it, and bring it to you, although he is surrounded by game. As there are two or three species of Newfoundland dog, it will be necessary to explain the description of dog calculated for the sportsman. This dog is generally black, and not so large as the common run of Newfoundland dogs; the head and nose are rather long, and sharp, deep chest, and fine legs, smooth hair, and does not curve his tail. Pool is the place to purchase them, and it is most preferable to buy one that has been trained. It is a faithful, and affectionate animal, and with gentle usage, extremely tractable.