The Neuroscience of Helmholtz and the Theories of Johannes Müller

In this, our continuation paper on Helmholtz and Müller, we examine Helmholtz’s contributions to sensation and perception, with emphasis on his extension and modification of Müller’s theory of specific nerve energies. The material is again presented in biographical-chronological context. We also examine Helmholtz’s views on depth and space perception, and his empirical theory of knowledge, which are also compared to Mutter’s views. It will be shown that Helmholtz remained stimulated by the thoughts and doctrines of Johannes Müller in the sensory-perceptual part of his career, which began early in the 1850s and ended with his death. Nevertheless, Helmholtz’s own experiments and new discoveries by others sometimes led him to quite different conclusions.     

The neuroscience of Helmholtz and the theories of Johannes Müller. Part 2: Sensation and perception

In this, our continuation paper on Helmholtz and Müller, we examine Helmholtz's contributions to sensation and perception, with emphasis on his extension and modification of Müller's theory of specific nerve energies. The material is again presented in biographical-chronological context. We also examine Helmholtz's views on depth and space perception, and his empirical theory of knowledge, which are also compared to Müller's views. It will be shown that Helmholtz remained stimulated by the thoughts and doctrines of Johannes Müller in the sensory-perceptual part of his career, which began early in the 1850s and ended with his death. Nevertheless, Helmholtz's own experiments and new discoveries by others sometimes led him to quite different conclusions.     

The neuroscience of Helmholtz and the theories of Johannes Müller. Part 1: Nerve cell structure,vitalism, and the nerve impulse

Hermann Helmholtz made monumental contributions to the neural sciences in the second half of the nineteenth century. Among his earliest achievements were experiments that challenged vitalism, microscopic studies on the structure of the nerve cell and its processes, and the first reasonable estimates of the speed of nerve transmission based on physiological experiments. In this, the first of a two-part article, we review Helmholtz's early contributions in biographical context and with reference to Johannes Müller's own thoughts. We reveal how Johannes Müller, considered by many to be the greatest physiologist of the first half of the nineteenth century, helped to launch and shape Helmholtz's career. We also show that Helmholtz was only willing to accept some of his mentor's theories, even though he had great admiration for Müller. The point will be made that Helmholtz owed a great debt to Müller, but even from his student days in Berlin he was an independent thinker with his own agenda, and never his strict disciple.     

The Neuroscience of Helmholtz and the Theories of Johannes Müller Part 1: Nerve Cell Structure,Vitalism, and the Nerve Impulse

Hermann Helmholtz made monumental contributions to the neural sciences in the second half of the nineteenth century. Among his earliest achievements were experiments that challenged vitalism, microscopic studies on the structure of the nerve cell and its processes, and the first reasonable estimates of the speed of nerve transmission based on physiological experiments. In this, the first of a two-part article, we review Helmholtz's early contributions in biographical context and with reference to Johannes Müller's own thoughts.We reveal how Johannes Müller, considered by many to be the greatest physiologist of the first half of the nineteenth century, helped to launch and shape Helmholtz's career. We also show that Helmholtz was only willing to accept some of his mentor's theories, even though he had great admiration for Müller. The point will be made that Helmholtz owed a great debt to Müller, but even from his student days in Berlin he was an independent thinker with his own agenda, and never his strict disciple.     

Johann August Philipp Gesner (1738–1801). A Review of His Essay “The Language Amnesia” in The Bicentennial Anniversary of His Death

On the 200th anniversary of Johann August Philipp Gesner's death, this paper summarizes and discusses a paper on language amnesia published in 1770. The author had clear knowledge of selective mental impairments resulting from brain diseases, and of separate mental representations for words and their underlying concepts. However, to explain the language impairment, Gesner suggested that it would not be caused by focal damage to a specific anatomic and functional unit of the mind, but is the consequence of a general sluggishness of the mental processes.     

The Indo‐European mirror: Monotheism and polytheism (J.G. Herder,E. Renan,A. Pictet,F.M. Müller and R.F. Grau)

Some authors assigned the Indo‐Europeans a mirror‐like role which allowed them to understand their own position with respect to contemporary Christian values. After dealing briefly with the writings of J.G. Herder, I shall evoke a certain number of questions which oriented the research of E. Renan, F.M. Müller, A. Pictet and R.F. Grau. The works of the latter authors expounded fabulous genealogies, organizing them into explanatory systems that radically opposed Hebrew monotheists to Indo‐European polytheists. Thus, depending on whether they had used the Semites or the Indo‐Europeans as their starting‐point, they concluded that monotheism or polytheism, respectively, was the archaic source of human thought. The goal on their horizon was a ressuscitated West, forever in the forefront of progress, often simultaneously Christian and scientific. If this type of historiographic analysis is urgently needed at the present time, its purpose is not to provide a grid for distinguishing “truth”; from “falsehood,”; but rather to grasp a set of scholarly traditions within its own channels of transmission.     

Criminalization of Homicide in Early Modern Denmark (16th–17th Centuries)

This article explores the criminalization of homicide in early modern Denmark, 16th–17th centuries. Criminalization is here defined, primarily, as the harshening of penalties for homicide in law and practice. The article shows that a process of criminalization took place that contributed to a pacification of the population (demonstrated by a decrease in homicides) but also engendered practices of resistance and evasion which were reminiscent of a medieval feud culture. The attitude towards homicide was for a long time ambivalent, not just among the lower classes but at all levels of society. Criminalization and pacification were mainly products of state-building through harsher punishment and the formation of a more reliable legal system. This top-down process meshed with the broader population’s demands for justice and security.     

Glass gilding process in medieval Syria and Egypt (13th–14th century)

Twelve gilded and enamelled Islamic glass fragments, produced in Syria or Egypt during the Ayyubid or Mamluk period, were provided by the Louvre museum for complete non-destructive analysis. The enamelling process of similar objects has been extensively studied in the last decades, but the gilding process has never been investigated in details. This paper focuses on the understanding of both the gilding process and the gold/glass adhesion mechanism. The structure, composition and thickness of the gold flakes forming the gilding decoration are measured. The complete process combining gilding and enamelling is described and the local mechanism of adhesion of gold flakes on the glass body is discussed.     

Johannes Janssonius’s Map of Dalmatia and the Ottoman–Venetian Borderland (1650)

The paper presents a comparative analysis of the map of Dalmatia by Johannes Janssonius and maps by his contemporaries. Janssonius’s cartographical models and the sources of the printed text accompanying his map are identified. The roles of Croatian cartographers and Venetian and Ottoman reports dealing with the border are uncovered. The importance of Janssonius’s map in disseminating knowledge about the little-known geography and history of Dalmatia, and the ways in which the map influenced perception of that country in the Ottoman Empire borderlands in general, are assessed.     

The analysis of two historic fired artificial stonewares: Coade stone (18th–19th centuries) and a recent discovery from Oxnead Hall,Norfolk (16th–17th centuries)

Coade stone has played a significant role in architectural and ornamental design since its inception in the early 18th century. It is well known that earlier, experimental, architectural stoneware products existed, but few of these have been studied in detail scientifically, and only one major analytical study of Coade stone has appeared in the literature. This paper presents a new spectroscopic analysis of Coade stone along with that of a newly discovered sample from Oxnead Hall in Norfolk where it known that Sir Clement Paston experimented with artificial stone in the late 16th century. The results demonstrate that it is possible to differentiate between the two variants on the basis of both the raw materials used and the different phases formed in their production processes.