Irwin says penicillin was discovered in a pot of hot water used to boil sweet corn. This was a common misconception in the 1950s. Penicillin's antibacterial properties were discovered when a fungal contaminant killed colonies on a laboratory streptococcal culture plate. Industrial production of penicillin required growing Penicillium mold in big vats of nutrient broth. The mold grew very poorly on most broths until someone tried adding corn steep liquor, a waste product of corn wet-milling. That increased mold growth 20 fold and made penicillin affordable.
Dick Van Dyke personally mentioned his top five favorite episodes, of the series' five season run. Where Did I Come From? (1962) is his all-time favorite. The four others are, The Attempted Marriage (1962), It May Look Like a Walnut (1963), I'd Rather Be Bald Than Have No Head at All (1964) and Never Bathe on Saturday (1965).