At this date we had travelled 88,000,000 miles since we left the earth, yet we knew it was there, level with our vessel, and only about 29,000,000 miles distant on our left hand, whilst Mars was only 7,000,000 miles from us on our right-hand side. Our position now was as follows:--Taking an imaginary line drawn from the _Areonal_ to Mars as the base line of an isosceles triangle, we were moving along the left side of the triangle, and Mars was moving in a slightly curved line along the right side. Our paths were therefore converging, and if all went well we should both meet at the apex of the triangle on the 24th September, as we had originally intended. We therefore had six clear days to cover the distance of less than 12,000,000 miles, so we should have sufficient time to slacken speed at the end of the journey. (See the chart.) Mars was rapidly growing in size and brightness, for the distance between the planet and the _Areonal_ was quickly diminishing as our paths converged, and the various markings on its almost full round disc formed the subject of continual observation and conversation. We had noticed on several occasions a mistiness on some parts of the planet, which I attributed to the vapours raised from the canals by the heated atmosphere. On the 21st of September, when we were all enjoying a smoke in the "evening," and conversation had dragged somewhat, John started us off on a fresh tack and gave us something to talk about for a very long time. He winked at M'Allister and, looking at me with a knowing smile, said: "Professor, as we are nearing our destination it might perhaps be well if you now gave us some detailed information respecting the planet, similar to that which you gave us when we were approaching the moon. It would be both interesting and useful; for we should learn much more from an orderly statement of the facts than we should from several long but desultory conversations." "Yes, Professor," chimed in M'Allister, "I'm quite ready to learn something definite about Mars, for I can't say I really know much about it at present." "Very well then," I replied, "it is upon your own heads, and if you are willing to listen to a rather long story, I am prepared to do the talking. Please remember, however, that it will require some time to make matters clear and understandable." "Fire away, mon," cried M'Allister, "we will listen as long as you care to talk." So I began--"Mars, as no doubt you are aware, is a much smaller planet than the earth, its diameter being only 4220 miles, which is a little less than twice the diameter of our moon.