Islands or Archipelagoes to mark their subsidence, and from the heated waters dense vapors arose enveloping the new Worlds as in winding sheets. As it is not possible to compute the ages, much less the years, during which Mars and Earth passed through the various stages of evolvement, up to the period when either Planet became sufficiently cool and stable, the waters of a suitable temperature and atmospheric conditions favorable to a degree that life in its earliest expression became possible, necessarily I must remain silent in relation to that matter. But in this connection I may say that the formative history of one Planet is the formative history of all Planets of all systems of Worlds. First, a nebulous condition of substance, which, through natural activities or laws, gradually contracts into measurable dimensions. Secondly, a somewhat spherical, gaseous body extending in all directions into space. Thirdly, a positive, individualized, observable body in a highly incandescent state, followed by such gradual evolvement as your geologists well understand. In a fragmentary and simplified fashion I have as concisely as possible replied to your _second_ question. As to the first, such authorities on our side of life as are known to be unquestionable, declare that the Planet Mars is incalculably older than Earth. That during the ages when our globe was almost wholly incandescent, Mars' crust was measurably solid and cooled and its earliest life expressions were teeming in its tepid waters. The interval elapsing between the earliest appearance of life on Mars and the period when it became possible for the earliest life expressions to appear on our Planet is not to be computed through years or through centuries of years, the duration of such an interval is inconceivable. We desire that you shall understand that _we do not propose_ that this shall be an astronomical, geological or other scientific work, but in so far as we may be able to use your organism we shall touch upon such recognized sciences as may subserve our purposes of comparing degrees of knowledge attained to, in the same direction by the peoples of two Planets, Mars and Earth. Medium--I should like to know how the lowest life forms of a new Planet originate, where do they come from, and what are they?