The mouth-blowpipe, after doing service for centuries to metal-workers as a soldering tool (hence the German name Löthrohr), in the hands of Gahn and subsequently of Berzelius became the most useful of instruments for the qualitative testing of mineral substances. Through the efforts of the latter, in fact, blowpipe analysis had developed into almost an independent branch of analysis. But nobody dreamt of quantitative mouth-blowpipe assaying until Harkortin 1827 (while a student in the Freiberg academy) succeeded in working out a blowpipe-assay for silver. Harkort stopped there; but the idea of blowpipe-assaying was taken up subsequently by Plattner, who, by bringing his characteristic thoroughness, indefatigability, and unexampled dexterity to bear on the subject, succeeded in working out reliable methods for all the ordinary useful metals. His modes of assaying for cobalt and nickel more especially quickly found favour with metallurgists, because they were more exact than the then known corresponding methods of “wet-way” analysis, and required a less number of hours than the latter required of days for their execution. Our analytical methods for the determination of cobalt have since become far more perfect but no less troublesome, and to the present day Plattner’s nickel-assay is the most precise method for the estimation of this metal in complex mixtures.

Plattner, while working at this specialty of his own, at the same time overhauled the entire field of qualitative blowpipe assaying, and ultimately summed up the whole of his vast experience in his Probirkunst mit dem Löthrohr, which soon became, and to the present day ranks as, the standard book on the subject. Since its first publication in 1835 the work has gone through four editions, apart from two independent English translations.

With all his high and recognized distinction in his own specialty, Plattner most keenly felt that his scientific education in Freiberg had been somewhat one-sided; and in 1839 he left his post and family to work for a year in Heinrich Rose’s laboratory in Berlin, and supplement his knowledge of modern methods of chemical analysis. While there as a student he at the same time acted as a teacher in his branch, and won the lasting friendship of a number of distinguished scientific men. On his return home in 1840 he was raised to the rank of assessor at the Government board of mining and metallurgy, and made chief of the royal department of· assaying. In 1842 he was deputed to complete a course of lectures on metallurgy in the Bergakademie which had been commenced by Lampadius; and he subsequently became Lampadius’s successor as professor of that branch, and for the then newly instituted course of blowpipe-assaying. In addition to these functions he instituted, in 1851, a special course on the metallurgy of iron. He continued lecturing in the academy as long as he was able,—until the session of 1856-57. It was during this period of professorial activity that he made the extensive studies and experimental researches which form the basis of his work Die metallurgischen Röstprocesse theoretisch betrachtet (Freiberg, 1856). His well-known Vorlesungen über allgemeine Hüttenkunde (vol. i. and ii., Freiberg, 1860) is a posthumous publication edited by Prof. Thomas Richter.

In addition to these great works (and the Probirkunst) Plattner published (in Erdmann!s Journal and in Schweigger ’ s Journal and elsewhere) numerous memoirs on metallurgical or mineralogical subjects, regarding which we must confine ourselves to saying that they mark him as an investigator of rare diligence and power. How he found time for all his original work is difficult to say; it certainly did not cause him to neglect his students. He attended to them in the most conscientious and efficient manner, as hundreds of his pupils all over the world can testify. His marked success as a teacher was no doubt owing greatly to his high personal qualities,—his cheerful, untiring, unselfish devotion to duty, his kindliness of heart and manner, his freedom from all cant and morbid ambition. The latter years of his life were embittered by intense suffering. After a long period of lingering illness he succumbed to a disease of the brain.