Leibknicht identifies the gas as one of the chlorides, phosgene. Most folks know phosgene from its use as gas warfare in WW1 (killed 85,000 solders in the trenches) and WW2 (used by the Japanese against Chinese soldiers and civilians). Phosgene was first made in 1812, and was quickly identified as deadly. Today, it is used extensively in the making of plastics. It kills by stopping the exchange of oxygen and CO2 across the alveolar membranes of the lungs. You suffocate.
When Loveless' uncle is introduced to West, his name is given as "Doctor Liebknicht". Translated literally from German, this is "love-not" (although in German, "nicht" is spelled without the 'k'), which means the same as Loveless.
Artemus tells Triste of the hardship of prisoners working in jute mills. In the late 1800s prisoners were often required to unravel, by hand, used ship's ropes and hawsers made fron jute fiber. These ropes were so fouled with tar that unraveling 3 pounds a day was counted as hard labor. The loose jute fibers with tar was called oakum and was the main waterproof caulking for shipbuilding and cast iron plumbing.
Dr Loveless' inventions were always far ahead of his time, one of the many reasons West admired him and even empathized with his hatred of humanity after being humiliated and insulted due to his height. It's what he was going to tell his "uncle" if he'd not been interrupted. Loveless also admired West, why he would never just allow him to be shot in an ordinary fashion but always chose something worthy of West as an adversary.
Guest stars are "Star Trek" alumni Susan Oliver, Michael Dunn and Anthony Caruso.