PÄRNUMAA KUTSEHARIDUSKESKUS EHITUSVIIMISTLEJA ALUMIINIUM Referaat Juhendaja: Anne Metsmaa Pärnu 2011 AVASTAMISE LUGU 1827. aastal sai välja paistev saksa keemik, hariduselt arst, Friedrich Wohler metalli, mida mitte keegi ei olnud kunagi näinud. Veidi varem sai seda metalli Oersted. Algul eraldas Wohler metalli keemilisest uhendist halli pulbrina, mis peenestamisel omandas metallilise läike. Katsed saada metalli kangina või suurte teradena jäid tulemusteta. Enne kui neid katseid kroonis 1845. aastal edu, kulus 18 aastat püsivaid otsinguid. Wohler sai uut metalli nööpnõela pea suuruste teradena. Väliselt oli ta sarnane hõbedaga, kuid erinevalt viimasest
itself, as an isolated phenomenon, neither borrowing from nor contributing to other bodies of knowledge. Frequency counts, linguistic characteristics, Kasiski examinations—all were peculiar and particular to cryptology. It dwelt a recluse in the world of science. Friedman led cryptology out of this lonely wilderness and into the broad rich domain of statistics. He connected cryptology to mathematics. The sense of expanding horizons must have resembled that felt by chemists when Friedrich Wohler synthesized urea, demonstrating that life processes operate under well-known chemical laws and are therefore subject to experimentation and control, and leading to today's vast strides in biochemistry. When Friedman subsumed cryptanalysis under statistics, he likewise flung wide the door to an armamentarium to which cryptology had never before had access. Its weapons—measures of central tendency and dispersion, of fit and
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