The Istituto e Museo di Storia della Scienza, Florence, Italy, possesses an astrolabe with five latitude plates that is now attributed to the Duisburg workshop of Gerard Mercator. Although it is known that Mercator made instruments, this is the first surviving example to be identified. Another latitude plate is shown to come from the workshop of the Florentine, Giovan Battista Giusti. A seventh plate, possibly engraved by Rumold Mercator, provides the only known Mercatorian polar stereographic projection. The role of (...) Egnazio Danti, cosmographer to the Grand Duke of Tuscany, in the acquisition of the astrolabe in about 1570 is considered. (shrink)

In a paper published in volume 50 of Annals of Science an astrolabe at the Istituto e Museo di Storia della Scienza, Florence, was attributed to the hand of Gerard Mercator, c. 1570, when his workshop was in Duisburg. This was the first scientific instrument by Mercator to be identified. Since then two further astrolabes by Mercator have been identified, one of them bearing his monogram: GMR. They belong to the Städtische Kunstsammlungen, Augsburg, and the Moravian Gallery, Brno. All (...) three instruments are described as a group, and reasons for believing that the Brno astrolabe was made earlier than 1550, and therefore in Louvain, are given. (shrink)

The concept of a technical frontier in branches of experimental measurement, such as the resolution of the microscope, angular measure and time telling, has been around for more than 60 years. The purpose of this brief paper is to identify the technical frontier operating on the achromatic astronomical telescope, where a limiting factor of the resolution of fine detail was the quality of the optical glass available. The achromatically corrected objective is formed from two kinds of glass, the common crown (...) glass and the heavy clear flint glass or lead glass. This last was difficult to make homogeneous, that is without regions of different density, and therefore different refraction and dispersion. Unusually, optical glass had to pass a second frontier, this time placed on the whole glass industry by the English Government in the form of excise duty, administered with a bureaucratic efficiency that effectively stopped, in around 1800, the making of optical glass suitable for the serious astronomical telescopes. The result of the tax imposition was to delay the English production of improved optical glass for more than 80 years. (shrink)

The general view is that there is one type of nocturnal, which is universal, first illustrated in a printed book in 1524. Recently, a number of quite differently constructed nocturnals has come to light. Six of these were made at the very beginning of the sixteenth century by Falcono of Bergamo in northern Italy. One of them, with the initials of the inventor, may well be the prototype. Five more are closely similar. Five further nocturnals of the same type have (...) been identified, but they are unsigned, and are not by Falcono. This paper establishes the existence of a hitherto unrecognized Italian workshop, and of a variant type of nocturnal. (shrink)

The aim of this paper is to investigate how alternative land ethics of agricultural stakeholders may help explain recent land use changes. The paper first explores the historical development of the land ethic concept in the United States and how those ethics have impacted land use policy and use of private lands. Secondly, primary data gathered from semi-structured interviews of farmers, ranchers, and influential stakeholders are then analyzed using stakeholder analysis methods to identify major factors considered in land use decisions, (...) priorities of factors of each group, and to define relevant mental models describing each group’s view of the land ethic concept. Results show that these stakeholder groups prioritize land use factors qualitatively differently and possess strikingly different land ethics. It is concluded that shifts in stakeholder land ethics have contributed to recent land use changes. Lastly, we discuss how current agricultural policy sends mixed signals about preferred land use and the potential ramifications based on the different land ethics we’ve described. (shrink)

Collapse is a term that has attracted much attention in social science literature in recent years, but there remain substantial areas of disagreement about how it should be understood in historical contexts. More specifically, the use of the term collapse often merely serves to dramatize long-past events, to push human actors into the background, and to mystify the past intellectually. At the same time, since human societies are complex systems, the alternative involves grasping the challenges that a holistic analysis presents, (...) taking account of the many different levels and paces at which societies function, and developing appropriate methods that help to integrate science and history. Often neglected elements in considerations of collapse are the perceptions and beliefs of a historical society and how a given society deals with change; an important facet of this, almost entirely ignored in the discussion, is the understanding of time held by the individuals and social groups affected by change; and from this perspective ‘collapse’ depends very much on perception, including the perceptions of the modern commentator. With this in mind, this article challenges simplistic notions of ‘collapse’ in an effort to encourage a more nuanced understanding of the impact and process of both social and environmental change on past human societies. (shrink)

This paper considers three essential gestures in Levinas’s theology, highlighting in each case how Levinas’s thinking allows him to either incorporate or sidestep some of the fiercest modern criticisms of traditional theism. First, we present Levinas’s vision of divine transcendence, outlining his ontological atheism and explaining how this obviates proving the existence of God and avoids the tangles of traditional theodicy. Second, we describe Levinas’s idea of the trace, showing how a nonexistent God still leaves its mark in the face (...) of the other person and explaining how this vision of divine immanence accords with the agendas of thinkers such as Feuerbach and Nietzsche, who criticized theology that elevated God while debasing humanity. Third, we present Levinas’s insistence on the philosophical primacy of ethics, showing how he infuses his ethical philosophy with religious themes, elevating moral philosophy to the level of ultimate concern in a way that even atheist social theoris. (shrink)