Born in Providence, Rhode Island, November 2, 1827, the son of Welcome Arnold and Sarah Gardner Greene, Thomas A. Greene was educated at the Friends' Boarding School of Providence, and the Fruit Hill Collegiate Institution in Smithfield, Rhode Island. At the age of sixteen, as a compromise with his father who wanted him to become a doctor, Thomas apprenticed to a retail drug firm in Providence and remained there for four years.
His employers were said to have been good chemists, and one was an enthusiastic botanist. When young Thomas received his certificate and set out for the middle west he was well qualified as a druggist and already interested in fossils and minerals. Stopping in New York to discuss the possibility of establishing a drug business with Henry H. Button, he proceeded to Chicago, Racine and Southport, and finally settled on Milwaukee as a good place in which to start his business. He bought the store of Henry Fess, Jr., and in the fall of 1848 Button joined him and the partnership of Greene and Button was established for the purpose of “... Carrying on the wholesale and retail drug business in Milwaukee, Wis. ...”
From its original assets of 5,000 dollars, the business prospered and in 1873, when younger members were admitted to the firm, the name was changed to Greene and Button Co. In its early years, the druggists did not employ salesmen. Once or twice a year one partner or the other made trips by rail or team to towns in southeastern Wisconsin, Mr. Greene usually going in the summer, and “Doc” Button in winter. Generally, Mr. Greene gave his attention to buying and selling, and Mr. Button had charge of finances. After the deaths of Dr. Button, 1890, and Mr. Greene, 1894, the corporation became known as Jerman, Pflueger and Kuehmsted Co., and in 1906 the corporate name was changed to Milwaukee Drug Company.
Having been influenced by his first employers in Providence in developing an interest in botany, Thomas A. Greene made many stops on his way west in 1848 to observe the flora of the region. As a druggist in Milwaukee, he became a collector not only of plants but also of minerals and fossils; and the hobby grew in scope as his success in business became more assured. His collection of minerals was outstanding for its completeness, and his fossils, according to his son-in-law, were considered to be “the most valuable ... [collection] west of Philadelphia.” In 1911, his children, Mrs. Horace A. J. Upham and Colonel Howard Greene, presented their father's collection of 75,000 to 100,000 specimens to Milwaukee-Downer College; and two years later the Thomas A. Greene Memorial Museum was dedicated on the campus.
Mr. Greene avidly collected specimens from early quarries, himself, and was in communication with geologists, supply houses, and other collectors all over the country, through whom he made purchases and exchanges. Through his reading and contacts with other collectors, he became acquainted with the leading paleontological authorities of the day, and exchanged letters with many of them, seeking information and advice. He was also in constant communication with supply houses from whom he obtained specimens.
