"The seed," Ralph explained, "is supplied to these tubes by means of compressed air. The tubes are perforated, and when air pressure is applied, the seed, flowing through the tubes is ejected evenly--just so many seeds to a given area. Closing the openings of the pipes automatically as the seeding proceeds, means only a given quantity of seed will fall upon any given square foot of soil. This makes for scientific planting, and we raise just the exact quantity of wheat we want." Alice watched the seed rain spellbound. Like a wall of rain it slowly receded into the distance until finally it disappeared. "How long does it take to sow this field?" she asked. "From two to three hours, depending upon the size of the field. This particular field is about eight miles long and three miles wide. The process should be completed within about three and a half hours." "And when will this crop be ready for the harvest?" Alice wanted to know. "In about seventy days from now the wheat will be ready to cut." Alice walked along thoughtfully and then inquired whether the great cost of such an undertaking would not make the growing of the foodstuffs prohibitive. "Quite the contrary," Ralph replied. "We are now growing wheat, corn, potatoes, and many other foodstuffs, for a much lower price than our ancestors did five or six hundred years ago. You see, it is the installation of the hothouses and machinery that is costly, but these glass and steel buildings will last for centuries with proper care. The frames are made of non-rusting steel which needs no painting. The glass lasts for hundreds of years. The labor we use in planting and harvesting is a mere fraction of what was used in olden times. Thus, for sowing and harvesting this plant, eight by three miles, we require only twenty people. This is a very much smaller number than was used on a small old-fashioned farm. "We waste nothing. We have no poor crops, and we get three or four times as much as our ancestors did." They stepped up to a glass case containing samples of wheat grown for hundreds of years, showing that a head of wheat grown in the year 1900 was about three inches long, while the present year's crop showed a length of more than six inches, or twice as much flour content per stalk. Ralph also pointed out to Alice that the modern wheat stalk was much bigger in circumference than the ancient ones, which, he explained, was attributable to the greater weight of the modern wheat. The old stalks could not possibly have supported such a great weight of grain, so it was necessary to cultivate bigger stalks.