"A few evenings ago, I paid a very pleasant visit to an old friend of Mr. Lewis's, which will afford me ample materials for this letter. He is what Mr. Lewis calls a _virtuoso_, which signifies, a person fond of antique and natural curiosities. You will, therefore, suppose I was not at a loss for amusement. In one cabinet was a number of stuffed birds and beasts; amongst others, a little animal somewhat resembling a rat, but rather smaller. It legs are short and slender; the fore-legs longer than the hind ones. Its head is of a pointed form; the colour of its body tawny, and variegated with large black spots, irregularly arranged; and the belly is white, tinged with yellow. There appeared to me so little that was uncommon in this animal, that I could not help asking Dr. Sinclair, on what account he had given it a place among so many curiosities. 'I value that little animal,' said he, 'as much as any in my collection. It is the Leming, or Lapland Marmot, and is distinguished from other quadrupeds, by habits peculiar to itself. It is only found in the northern part of our continent, where immense numbers of these little animals sometimes overspread large tracts of country, especially in Lapland, Sweden, and Norway. Their appearance happens at uncertain periods; but fortunately for the inhabitants of these countries, not oftener than once or twice in twenty years. As the source whence they originate in such astonishing numbers, is as yet unexplored by the naturalist, it is no wonder that the ignorant Laplander should seriously believe that they are rained from the clouds. Myriads of these animals pour down from the mountains, and form an overwhelming troop, which nothing can resist. The disposition of their march is generally in lines, about three feet asunder, and exactly parallel. In this order they advance with as much regularity as a well-disciplined army; and, it is remarked, that their course is from the north-west or south-east. They frequently cover the extent of a square mile, travelling in the night. They always halt in the day, and in the evening resume their march. No opposition can stop them; and, whatever way their course is directed, neither fire not water can turn them out of their road. If a lake or river intercept their progress, they will swim across, or perish in the attempt; if a fire interrupt their course, they instantly plunge into the flames; if a well, they dart down into it; if a hay-rick, they eat through it; and, if a house stand in their way, they either attempt to climb over it, or eat through it; but, if both be impracticable, they will rather die with famine before it, than turn out of the way. If thousands perish, thousands still supply their place, until the whole column be destroyed. Wherever they pass, they annihilate every trace of vegetation, and, when subsistence fails, are said to divide into two different armies, which engage with the most deadly hostility, and