Penicillin nontoxic in humans by first performing toxicity tests in animals and then on humans. His subsequent experiments on penicillin's response to heat and pH allowed Fleming to increase the stability of the compound. The one test that modern scientists would find missing from his work was the test of penicillin on an infected animal, the results of which would likely have sparked great interest in penicillin and sped its development by almost a decade. The importance of his work has been recognized by the placement of an International Historic Chemical Landmark at the Alexander Fleming Laboratory Museum in London on
Perfect Day (1929 film) was written in May 1929 and filmed between June 1–8, 1929. The original 1929 release of "Perfect Day" contained no music other than that used over the opening credits. The Roach Studios would reissue the film in 1937 with an added music score being utilized at the time in other Roach comedies. The 1929 version was considered lost until the 2011 DVD release "Laurel and Hardy: The Essential Collection", when the original Vitaphone disc track sans the incidental music became available. Adding the soundtrack in 1937 to the existing film resulted in a slight reduction of the correct frame ratio: