The things most to be dreaded were sudden noises; thunder-storms; and above all a drop in temperature, since chilly surroundings congealed the fluid silk in the ducts at each side of the silkworm, rendering it too thick for the creature to spin into fibre.
The noise and the temperature could to an extent be controlled. But the thunder-storms! Those were another matter.
Anxiously the Bretton family studied every passing cloud.
"If a severe storm should wreck our crop now—at the very end—it would be cruel!" declared Pierre. "No matter how careful we are we cannot prevent some great black thunder-head from rolling over the mountains and down through the valley."
"It is useless to worry, dear," answered his mother. "If such a storm comes it will be through no fault of ours."
"It would raise havoc in our harvest just the same," cut in Josef. "The vibrations of thunder sound worse among the metal shelves. They catch the jar, and seem to hold and echo it. Your father told me about a man near Tours who had lightning wires along his shelves to protect his silkworms from electric currents. The wires carried off the worst of the vibration."
"I wish we could afford to equip our silk-house that way," said Marie.
"Just wait until we get rich. Maybe some day we can," answered Pierre gaily.
Fortunately for the Brettons' silkworms, however, no electrical storm came.
The caterpillars climbed serenely into the brush arches above their heads, selected spots that pleased their fancy, and began constructing their cocoons. First came the loose, web-like oval within which the cocoon itself was to be made. This was the work of the first day and its construction was of what is known as floss. Then followed the yellow, compact cocoon requiring three or four days for its spinning. Occasionally two worms would insist upon spinning together, crossing and recrossing their threads; these double cocoons always had to be sorted out from the others, however, as the silk could not be wound off them easily.