Definite proof of the Planet Mars being uninhabited is shown by recent astronomical investigation according to Loring B. Andrews, instructor in Astronomy who spoke at a public "Open Nights" lecture at the Observatory last night. He revealed that recent evidence shows the atmosphere of the planet too slight to sustain life.

"The old question, 'Is there life on Mars?' ", said Dr. Andrews, "has been definitely decided by recent observational evidence which shows the atmosphere of the planet contains but one quarter of one percent as much oxygen as does the earth's atmosphere at sea level. Human beings, such as inhabit the earth, would find life very difficult, far more extreme than the lack of oxygen at the top of high mountains."

From scientific investigation in the past it has been known that the atmosphere would be less than one quarter as dense as that of the earth. Whether this condition would prohibit life as we know it had been an open question among astronomers.

The question of life on Mars has been open ever since the time that the Italian astronomer, Schiaparelil, first observed a network of very fine lines on the planet's surface. These he called 'canale' in the report of his discovery to the astronomical world. The word which means "channel" was mistranslated as "canal" in both the English and French versions of his report.

The thought of artificial construction on the surface of Mars at once caught the fancy of many astronomers of the period and Porcival Lowell '76, in particular began an intensive study of the planet. Spectroscopic comparisons of the planet and the Moon by Dr. Silpher at the Lowell Observatory gave what seemed to be decisive evidence of water vapor in the atmosphere.

At once, the search for clouds, definite proof of the existence of water vapor, began. The presence of certain white spots was explained away by one astronomer as nothing more than mountains reaching the plausible elevation of two miles. This could not explain the phenomenon witnessed at the Lowell Observatory on the evening of May 26, 1903 however.

At that time, Dr. Silpher saw a projection, 300 miles in length, the highest point of which extended upwards into the atmosphere some 17 miles. The body was tawny in color. That a cloud could rise so high in such a rarified atmosphere seemed unlikely. The explanation for it was that it was probably a cloud of dust swept from the arid regions of the temperate zone. Recent dust clouds in the middle west of America have reached vastly larger proportions.

Lowell founded an observatory in Flagstaff, Arizona, a region admirably suited for the examination of the heavens, and equipped it with a 24-inch telescope, of which the main purpose was to carry on the investigation of Mars. Here a careful study of the "canals" began. As a result, by 1908. five hundred and seventy-five such markings had been mapped.

The canals ran in a definitely ordered scheme, sometimes in pairs, connecting the old sea floors, that seemed to contain vegetation, with one another. At Flagstaff, the most favorably situated point of observation, these canals are seen clearly as fine, sharp lines. Elsewhere, they are blurred, diffuse, and fewer are visible.

The thickness of the lines seems to vary seasonally, as do the small dots which mark their intersections. This would seem to prove a waxing and waning vegetation along their banks which flourishes and dier as the polar ice caps melt and collect again, which occurs every year.

Whether the "canals" are any more than an optical illusion is, perhaps, doubtful. The great difficulty there is in pronouncing on their reality is due to the fact that the astronomer is dealing with objects not plainly visible. To quote the Encyclopedia Britannica, "the question becomes one of psychological optics rather than astronomy."

The mean temperature of Mars is 48 degrees Fahrenheit, a temperature which has great fluctuations from summer to winter. Severe as these are, they do not exceed those of Northern Canada in the Yokon district. Thus weather conditions did not preclude life.

If their reality is not questioned, then it seems at least possible that there was once life on the planet. In the past there was probably a greater abundance of oxygen, the only factor that forbids the present existence of life