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JAMA. 1927;88(7):484-485. doi:10.1001/jama.1927.02680330036014.
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Nearly sixty years ago, Boettcher1 described the preparation of a crystalline substance from human semen. Through this discovery the name "Boettcher's crystals" came into notice. Subsequently Schreiner2 demonstrated that these represent a compound of phosphoric acid with an organic base, afterward designated "spermine." It is a singular fact that the crystals of spermine phosphate had evidently been seen and depicted by Leeuwenhoek, the pioneer microscopist, in 1678, and rediscovered and accurately described anew by Vauquelin in 1791. Other investigators may have seen the same crystals, but Schreiner was apparently the first to recognize their true nature.

At one time the statement was current that the characteristic odor of semen is attributable to the disintegration of spermine. The Russian physiologist Alexander von Poehl also reported, about 1890, that he had isolated spermine phosphate from testis and other organs. It was his writings in particular that brought the substance into


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