"It's something a big commercial laboratory managed to produce for abstract reasons," he answered. "It isn't any one substance, but its structure does include quite a few complex silicone compounds. Chemically it's not static. Processes and structural changes are going on inside it constantly. Its microscopic texture is cellular, like animal tissue. Pour, say, sugar dissolved in water on it, with the addition of certain salts, and it absorbs the solution slowly, along with oxygen from the air, to produce a kind of tissue-combustion, heat and movement. But it can convert sunlight, or simple heat from an outside source, or electricity, into motion, too. And it grows. Cut a piece of it off, and that will grow, too, as if reproduction had occurred. So--would you call it life of a sort? It's a lot more rugged than common life. Here, I'll show you, Charlie...." Doc picked up a small soldering tool. When its point glowed red hot he held it close to that pinkish oblong. It did not recoil from the heat. Instead, as if impelled by some inherent automatism or instinct, it curled itself around the tool, and, hissing softly, seemed to enjoy the warmth. When Doc switched off the current, it uncoiled itself as if in disappointment. It wasn't burned. "Cold it is equally resistant," Doc remarked. "Especially when its vital fluid, moistening it inside and out, is changed to something with a lower freezing temperature than water. Alcohol, for example, or liquefied air or ammonia gas. Then its chemistry, and the flow of energy continue on a different temperature plane, for it is supremely adaptable, Charlie." Dr. Lanvin's sly expression matched the chill along my back. "Okay," I growled. "Now tell me what you're _really_ thinking." He shrugged. "Oh, nothing definite, Charlie. Someday reaching the stars in another figurative sense, maybe. As is, this stuff isn't of much use. Call it 'protoplast' as its creators do--a tougher, upstart brother of protoplasm--life. It isn't molded. But what if, in a vastly improved form, if could be someday?" I frowned. "An animal?" I questioned. "Artificially made? Or--a man? An android, that is? Pure fantasy, of course, yet. A robot, with a robot's ruggedness, but made completely in human form. Servants maybe?" Doc Lanvin's mild grin turned crooked. "Servants?" he challenged. "Is that all? What if we were living the last century of man's existence as original man? No, I don't necessarily mean the often dreamed-up possibility of a robot conquest of humanity by force! But what of the 'improved model' principle, applied by humans to themselves, with the transfer of mind and ego to a body that could live without harm in the cold vacuum between the planets, or in an inferno; a body unaging, and destructible only by absolute violence? No, Charlie, this development must normally be a long ways ahead. But what if?" A cold tingling had started around my heart, spreading inexorably to the tips of my fingers, toes, and tongue.