Incorporated in Philadelphia in 1891, H. K. Mulford Company initially mass-produced some 800 different medical products. Their largest seller was a water-soluble pill made possible by their patented tableting machine. With von Behring’s diphtheria antitoxin discovery, however, the owners recognized the potential for a lucrative new venture in biologics. The change in the business model towards biologics required new hires. In 1894 Joseph McFarland, a noted bacteriologist and pathologist at the University of Pennsylvania, became the first major hire for this new endeavor, and a year later Mulford produced the first commercial diphtheria antitoxin in the country. The antitoxin was an immediate commercial success and the company quickly began expanding the business to other biologicals. This expansion included constructing new laboratories for biological, vaccine, and veterinary research, hiring trained scientists—including physicians, pharmacists, chemists, veterinarians, and botanists—and relocating to a larger property. In 1896 the company moved to a 200-acre farm in Glenolden, Pennsylvania, eight miles outside the city limits, and by 1920 the new site had nearly 1,000 employees and 52 buildings, including stables and barns for the hundreds of horses, cows, and smaller animals. During the 1920s Mulford specialized in human and veterinary serums, antitoxins, and vaccines, and in 1929 they merged with Sharpe & Dohme, Inc. of Baltimore.