and sea-voyages were safe and easy even before Martial ingenuity devised vessels which are almost independent of weather.  During the greater part of the year a clear sky from the morning to the evening zyda may be reckoned upon with almost absolute confidence.  A heavy dew, thoroughly watering the whole surface, rendering the rarity of rain no inconvenience to agriculture, falls during the earlier hours of the night, which nevertheless remains cloudy; while the periods of sunset and sunrise are, as I have already said, marked almost invariably by dense mist, extending from one to four thousand feet above the sea-level, according to latitude and season.  From the dissipation of the morning to the fall of the evening mist, the tropical temperature ranges, according to the time of the day and year, from 24 deg. to 35 deg.  C. A very sudden change takes place at sunset.  Except within 28 deg. of the Equator, night frosts prevail during no small part of the year.  Fine nights are at all times chilly, and men employed out of doors from the fall of the evening to the dispersal of the morning mists rely on an unusually warm under-dress of soft leather, as flexible as kid, but thicker, which is said to keep in the warmth of the body far better than any woven material.  Women who, from whatever reason, venture out at night, wear the warmest cloaks they can procure.  Those of limited means wear a loosely woven hair or woollen over-robe in lieu of their usual outdoor garment, resembling tufted cotton.  Those who can afford them substitute for the envelope of down, described a while back, warm skin or fur overgarments, obtained from the sub-arctic lands and seas, and furnished sometimes by a creature not very unlike our Polar bear, but passing half his time in the water and living on fish; sometimes by a mammal more resembling something intermediate between the mammoth and the walrus, with the habits of the hippopotamus and a fur not unlike the sealskin so much affected in Europe.

Outside the city, at a distance protecting it from any unpleasant vapours, which besides were carried up metallic tubes of enormous height, were several factories of great extent, some chemical, some textile, others reducing from their ores, purifying, forging, and producing in bulk and forms convenient for their various uses, the numerous metals employed in Mars.  The most important of these—­zorinta—­is obtained from a tenacious soil much resembling our own clay. [12] It is far lighter than tin, has the colour and lustre of silver, and never tarnishes, the only rust produced by oxidation of its surface being a white loose powder, which can be brushed or shaken off without difficulty.  Of this nearly all Martial utensils and furniture are constructed; and its susceptibility to the electric current renders it especially useful for mechanical purposes, electricity supplying the chief if not the sole motive-power employed in Martial industry.  The largest factories, however,