DVT 151, 3
150 let od prezentace výsledků experimentálních výzkumů Gregora J. Mendela
Michal V. Šimůnek
150 years since the presentation of results of G. J. Mendel’s experimental
This concise essay reflects on the 150th anniversary of the presentations of the results of Mendel’s experiments against the background of the formation of the study of genetics during the 20th century.
Key-words: Gregor J. Mendel ● history of genetics ● heredity
Summary: The text recalls how the commemoration of successive anniversaries of Gregor Johann Mendel (1822–1884) during the 20th century, especially the anniversary of his birth (1922) and the publication his long-time experiments with plant hybrids (1965), mirrored changing eras, the development of the field of genetics, and emergence of the other disciplines derived from genetics. The anniversaries connected with Mendel’s life and work were historically important and even acted as catalysts for further developments in the field.
DVT 151, 6
Od medicíny k botanice: milník Zalužanský
Lucie Čermáková – Jan Janko
From Medicine to Botany – Milestone Zalužanský.
A number of Czech researchers have been devoting their attention to the personality and work of Adam Zalužanský of Zalužany, yet the examination and evaluation of his most interesting work – the botanical treatise Methodi herbariae libri tres – is still insufficient. Somehow the chapter on plant sexuality has been overestimated, although it does not hold any outstanding position either in the treatise itself or in the realm of Renaissance botany.
This paper outlines the state of botanical knowledge in the sixteenth century and discusses Zalužanský’s work in this context. It introduces authors and concepts that could have inspired or influenced the work of Adam Zalužanský. Concerning the treatise itself, we focus on features that are considered new and progressive in the realm of botanical inquiry – the methodological approach to the botanical subject, its emancipation from medicine and other disciplines, and the attempt to systematize particular plant species.
Key words: Adam Zalužanský of Zalužany ● renaissance ● history of botany ● plant systematics
Summary: Zalužanský made a clear demand to separate botany from medicine and to subordinate it to physics in the Aristotelian sense. Botany was thus understood as an independent discipline, which was, however, to a large degree still confused, unclear, and full of disagreements. Therefore, Zalužanský (in the context of other botanical treatises of sixteenth century) suggested his own methodical approach. his approach to studying, describing, and classifying plants is a milestone in the history of botany, but surprisingly his work did not receive a great response.
DVT 151, 25
Pýthagorova tabule v raném latinském středověku
Pythagorean board in the Early Latin Middle Ages.
This paper deals with a useful mathematical tool called ‘mensa pythagorica’ or ‘abacus’. Mathematicians of the Latin Christian West used this tool most extensively from the end of 10th century to the 12th century. This article analyzes two descriptions of this tool in two texts written around the year 1000 and also presents eight images of the abacus from the manuscripts of this epoch – i.e. from the end of the 10th century to the beginning of 12th century.
Keywords: abacus ● mathematics ● calculations in the Early Christian Latin World
This paper presents the abacus of the Latin pre-scholastic Middle Ages. With
the use of the two oldest surviving descriptions of the abacus (by Richer of
Reims and Bernelius the younger from Paris) together with the oldest images
of the calculating tool preserved in manuscripts from the end of the 10 th and
beginning of the 12 th centuries (so called abacus from Echternach; the abacus
from Bern; the abacus from Paris from the beginning of 11 th century; abacus
from so called pseudo-Boethius Geometry II; the abacus from Vatican; the abacus
from Rouen; the abacus from Paris from the 11 th Century, the abacus from
Oxford and so called abacus of Abbo) this article introduces in detail the
arithmetic tool that proved a source of great fascination for many intellectuals
in its time.
This text describes and analyzes the individual parts of the abacus, while emphasizing the descriptions and surviving images of this tool and comparing them to each other. Furthermore, the text presents and explains the complementary mathematical information emerging from the images of the abacuses in manuscripts (abacistic symbols and names of numerals, markings of the abacus columns, and symbols of fractions and relations between them).