The pheromonal tests were complex, but not impossibly difficult. The first of the ten pheromones was a simple grouping stimulus, causing large numbers of workers to gather as the chemical was spread from palp to palp. The workers then waited for further instructions; if none were forthcoming, they dispersed. To work effectively, the pheromones had to be given in a mix, or series, like computer commands; number one, grouping, for instance, together with the third pheromone, a transferral order, which caused the workers to empty any given chamber and move its effects to another. The ninth pheromone had the best industrial possibilities; it was a building order, causing the workers to gather tunnelers and dredgers and set them to work. Others were annoying; the tenth pheromone provoked grooming behavior, and the workers’ furry palps stripped off the remaining rags of Afriel’s clothing. The eighth pheromone sent the workers off to harvest material on the asteroid’s surface, and in their eagerness to observe its effects the two explorers were almost trapped and swept off into space.