Potassium Permanganate Bleaching of an 18th-Century Hand-Coloured Aquatint Print

Author(s):  
Martin Strebel

AbstractThe treatment of a large-scale late 18th-century landscape view is described, focussing on a bleaching treatment. The hand-coloured aquatint Panorama de Chaumont is owned by the Bibliothèque cantonale et universitaire in Neuchâtel, Switzerland. It had been mounted on a wooden strainer and framed without glazing; severe and uneven browning made it unsuitable for presentation. The discolouration resulted from light exposure and direct contact with a wooden strainer which released volatile organic compounds. To minimize the discolouration, the six parts of the print were dismounted and separated along the joints from each other. The pieces were deacidified in tap water. Only one segment was bleached at first with a 0.1% potassium permanganate solution. However, large areas of blue colouring were decolourized during the subsequent sodium dithionite treatment. The decolourized areas of the print recovered their previous blue tone during the following rinsing in water and drying. The unexpected effect was caused by the reduction of indigo to indigo white (leuco-indigo) and its subsequent re-oxidation to indigo in absence of the reducing agent and through impact of atmospheric oxygen. Being able to assess the variables after a first testing phase, all print segments were finally bleached with a 1% potassium permanganate solution. The sheets were deacidified aqueously, resized on the verso with a 0.8% gelatine solution and tears were repaired. The image segments were not rejoined contrary to conservation recommendations.

2011 ◽  
Vol 7 (5) ◽  
pp. 3399-3448
Author(s):  
M. J. Alcoforado ◽  
J. M. Vaquero ◽  
R. M. Trigo ◽  
J. P. Taborda

Abstract. Natural proxies, documentary evidence and instrumental data are the main sources used to reconstruct past climates. In this paper, we present the 18th century meteorologists (either Portuguese or foreigners), who made the first observations at several sites in Continental Portugal, Madeira Island and Rio de Janeiro (Brazil), from 1749 until 1802. Information is given concerning observation site, variables observed, measurement period, methodologies and sources (both manuscript and printed). Some examples from the data usefulness are given: rainfall variability in Madeira (1749–1753) and in Continental Portugal (1781–1793) was reconstructed, allowing to extend towards the late 18th century the well known negative correlation between the NAO index and seasonal rainfall. Furthermore, previously unpublished data for 1783–1784 has allowed analysing the consequences of the Laki eruption in Portugal: foggy and haze days are referred to in summer 1783, but unlike the hot summer observed in Northern and Central Europe, temperatures in Portugal were lower than average. Additionally, observations from Rio de Janeiro in Brazil show that the Laki consequences may well have spread to sectors of the Southern Hemisphere. Although the series are short, the data will be used for climate reconstruction studies focused in Southern Portugal and are also useful to improve the quality of large scale reconstruction datasets.


Author(s):  
João Paulo Cabral

Resumo As primeiras observações e recolhas de eucaliptos ocorreram nas grandes viagens inglesas e francesas ao Pacífico, em particular à Austrália, em finais do século XVIII. O género Eucalyptus L'Hér. foi estabelecido em 1788, e logo nas duas décadas seguintes seriam descritas, por botânicos franceses e ingleses, muitas espécies novas. O primeiro eucalipto cultivado em Inglaterra foi trazido, em 1774, na segunda viagem de James Cook. Em França, a introdução terá sido feita em 1804, no Jardim Botânico de Montpellier, na Alemanha em 1809, no Jardim Botânico de Berlim, e em Itália, em 1813, no Jardim Botânico de Nápoles. Em Portugal, a introdução do eucalipto foi muito posterior a estas datas. Na propriedade do duque de Palmela no Lumiar, foram plantados dois eucaliptos em 1850-1852. No Horto Botânico da Escola Médico-Cirúrgica de Lisboa, existia em 1852, pelo menos um espécimen, certamente para uso ou demonstração das suas propriedades terapêuticas. A partir da década de 1860, a expansão foi muito rápida. Em 1869, a companhia real dos caminhos-de-ferro portugueses iniciou a plantação de eucaliptos nas estações, casas de guarda e ao longo da via-férrea. As primeiras plantações em larga escala terão ocorrido na década de 1880 em propriedades perto de Abrantes arrendadas por William T. Tait. Em 1886 estavam já plantados 150 mil eucaliptos. Nesta mesma década começou a plantação, em escala apreciável, de eucaliptos nas Matas Nacionais. Em finais do século XX, tinham sido introduzidas em Portugal cerca de 250 espécies, sendo o Eucalyptus globulus Labill., a espécie largamente dominante. É interessante constatar que tendo sido um dos países europeus que mais tarde introduziu a cultura do eucalipto, Portugal é hoje, a nível mundial, um dos que apresenta maior percentagem da sua área florestal dedicada a esta cultura.Palavras-chave: eucalipto; jardins botânicos; Portugal. Abstract The earliest observations and collections of eucalypts occurred on the great English and French voyages to the Pacific, particularly Australia, in the late 18th century. The genus Eucalyptus L'Hér. was described in 1788, and soon in the following two decades, many species would be described by French and English botanists. The first eucalypt grown in England was brought in 1774 on James Cook's second voyage. In France, the introduction seems to have occurred in 1804, at the Botanical Garden of Montpellier, in Germany in 1809, at the Botanical Garden of Berlin, and in Italy, in 1813, at the Botanical Garden of Naples. In Portugal, the introduction of eucalypts was much later than these dates. In the property of the Duke of Palmela in Lumiar, two eucalypts were planted in 1850-1852. The Botanical Garden of the Medical-Surgical School of Lisbon had in 1852, at least one specimen, certainly for use or demonstration of its therapeutic properties. From the 1860s the expansion was very rapid. In 1869, the royal company of the Portuguese railways began planting eucalypts in the stations, guard houses and along the railroad. The first large-scale plantations occurred in the 1880s in properties near Abrantes leased by William T. Tait. By 1886, 150,000 eucalypts were already planted. In the same decade began the planting, on an appreciable scale, of eucalypts in “Matas Nacionais”. By the end of the 20th century about 250 species had been introduced in Portugal, being Eucalyptus globulus Labill., the species largely dominant. It is interesting to note that Portugal, one of the European countries that later introduced the eucalypt, is today, worldwide, one of the countries with the highest percentage of its forest area dedicated to this culture. Keywords: eucalypt; botanical gardens; Portugal.


2012 ◽  
Vol 8 (1) ◽  
pp. 353-371 ◽  
Author(s):  
M. J. Alcoforado ◽  
J. M. Vaquero ◽  
R. M. Trigo ◽  
J. P. Taborda

Abstract. Natural proxies, documentary evidence and instrumental data are the only sources used to reconstruct past climates. In this paper, we present the 18th century meteorologists (either Portuguese or foreigners) who made the first observations at several sites in Continental Portugal, Madeira Island and Rio de Janeiro (Brazil), from 1749 until 1802. Information is given concerning observation site, variables observed, measurement period, methods of measurements and sources (both manuscript and printed). Some examples from the data usefulness are given: rainfall variability in Madeira (1749–1753) and in continental Portugal (1781–1793) was reconstructed, allowing to extend towards the late 18th century the well known negative correlation between the NAO index and seasonal rainfall. Furthermore, previously unpublished data for 1783–1784 have allowed analysing the consequences of the Lakagígar eruption in Portugal: foggy and haze days are referred to in summer 1783, but unlike the hot summer observed in northern and central Europe, temperatures in Portugal were lower than average. Additionally, observations from Rio de Janeiro in Brazil show that the Lakagígar consequences may well have spread to sectors of the Southern Hemisphere. Although the series are short, the data have been used for climate reconstruction studies and may also be useful to improve the quality of large scale reconstruction datasets.


2013 ◽  
Vol 10 (6) ◽  
pp. 7517-7536 ◽  
Author(s):  
J. L. Wescoat

Abstract. This paper assesses changing norms of water use known as the duty of water. It is a case study in historical socio-hydrology, a line of research useful for anticipating changing social values with respect to water. The duty of water is currently defined as the amount of water reasonably required to irrigate a substantial crop with careful management and without waste on a given tract of land. The historical section of the paper traces this concept back to late-18th century analysis of steam engine efficiencies for mine dewatering in Britain. A half-century later, British irrigation engineers fundamentally altered the concept of duty to plan large-scale canal irrigation systems in northern India at an average duty of 218 acres per cubic foot per second (cfs). They justified this extensive irrigation standard (i.e., low water application rate over large areas) with a suite of social values that linked famine prevention with revenue generation and territorial control. Several decades later irrigation engineers in the western US adapted the duty of water concept to a different socio-hydrologic system and norms, using it to establish minimum standards for water rights appropriation (e.g., only 40 to 80 acres per cfs). The final section shows that while the duty of water concept has now been eclipsed by other measures and standards of water efficiency, it may have continuing relevance for anticipating if not predicting emerging social values with respect to water.


2006 ◽  
Vol 23 (2) ◽  
pp. 263-306 ◽  
Author(s):  
SU YIN MAK

ABSTRACT Although recent scholarship has witnessed a welcome disavowal of the view that Schubert's formal and tonal designs in sonata form compositions bespeak the song composer's inability to master large-scale instrumental genres, it remains a commonplace to characterize Schubert's unorthodox practice as ““lyrical.”” Yet the historical, theoretical, and aesthetic bases of this lyricism have received little critical attention. A systematic and historically grounded approach to the notion of lyrical form in Schubert may be established by appealing to the rhetorical distinction between hypotaxis and parataxis, which pervaded late 18th-century discussions of both music and language. In particular, parataxis, a style that deliberately omits syntactical connections and relies instead on juxtaposition and parallelism, offers a suggestive technical link between Schubert's instrumental practice and the discursive techniques of contemporaneous lyric poetry. There are also aesthetic connections between idealist views of the lyric and the composer's own artistic beliefs, as confirmed by biographical documents. Schubert's approach to form was as much informed by these literary sensibilities as by the Classical compositional tradition. Like poets for whom the lyric served both as an Arcadian ideal of song and as an alternative to the prosaic realities of the present, Schubert evoked the lyric within the context of the sonata as a means of reunifying the dissociated sensibility of the Enlightenment. In so doing, he secured a place for the poetic imagination in instrumental music.


Author(s):  
M. S. Bischel ◽  
J. M. Schultz

Despite its rapidly growing use in commercial applications, the morphology of LLDPE and its blends has not been thoroughly studied by microscopy techniques. As part of a study to examine the morphology of a LLDPE narrow fraction and its blends with HDPE via SEM, TEM and AFM, an appropriate etchant is required. However, no satisfactory recipes could be found in the literature. Mirabella used n-heptane, a solvent for LLDPE, as an etchant to reveal certain morphological features in the SEM, including faint banding in spherulites. A 1992 paper by Bassett included a TEM micrograph of an axialite of LLDPE, etched in a potassium permanganate solution, but no details were given.Attempts to use n-heptane, at 60°C, as an etchant were unsuccessful: depending upon thickness, samples swelled and increased in diameter by 5-10% or more within 15 minutes. Attempts to use the standard 3.5% potassium permanganate solution for HDPE were also unsuccessful: the LLDPE was severely overetched. Weaker solutions were also too severe.


Author(s):  
M. McNEIL

Erasmus Darwin was the focus and embodiment of provincial England in his day. Renowned as a physician, he spent much of his life at Lichfield. He instigated the founding of the Lichfield Botanic Society, which provided the first English translation of the works of Linnaeus, and established a botanic garden; the Lunar Society of Birmingham; the Derby Philosophical Society; and two provincial libraries. A list of Darwin's correspondents and associates reads like a "who's who" of eighteenth century science, industry, medicine and philosophy. His poetry was also well received by his contemporaries and he expounded the evolutionary principles of life. Darwin can be seen as an English equivalent of Lamarck, being a philosopher of nature and human society. His ideas have been linked to a multitude of movements, including the nosological movement in Western medicine, nineteenth century utilitarianism, Romanticism in both Britain and Germany, and associationist psychology. The relationships between various aspects of Darwin's interests and the organizational principles of his writings were examined. His poetical form and medical theory were not peripheral to his study of nature but intrinsically linked in providing his contemporaries with a panorama of nature. A richer, more integrated comprehension of Erasmus Darwin as one of the most significant and representative personalities of his era was presented.


2017 ◽  
Vol 15 (2) ◽  
pp. 175-185
Author(s):  
Edyta Sokalska

The reception of common law in the United States was stimulated by a very popular and influential treatise Commentaries on the Laws of England by Sir William Blackstone, published in the late 18th century. The work of Blackstone strengthened the continued reception of the common law from the American colonies into the constituent states. Because of the large measure of sovereignty of the states, common law had not exactly developed in the same way in every state. Despite the fact that a single common law was originally exported from England to America, a great variety of factors had led to the development of different common law rules in different states. Albert W. Alschuler from University of Chicago Law School is one of the contemporary American professors of law. The part of his works can be assumed as academic historical-legal narrations, especially those concerning Blackstone: Rediscovering Blackstone and Sir William Blackstone and the Shaping of American Law. Alschuler argues that Blackstone’s Commentaries inspired the evolution of American and British law. He introduces not only the profile of William Blackstone, but also examines to which extent the concepts of Blackstone have become the basis for the development of the American legal thought.


2019 ◽  
Vol 63 (2) ◽  
pp. 187-204
Author(s):  
Carolin Rocks

"Praktiken zur Autonomie Zu Moritz’ Über die bildende Nachahmung des Schönen Karl Philipp Moritz’ Über die bildende Nachahmung des Schönen (1788) gilt als der autonomieästhetischeProgrammtext in der zweiten Hälfte des 18. Jahrhunderts. DerAufsatz stellt diese ästhetikgeschichtliche Klassifikation nicht in Frage, zeigt aber,dass die im Kern unbestreitbar kunstmetaphysische Argumentation über ethischePraktiken begründet wird. Diese Praktiken nehmen in der Arbeit an der Autonomieeinen so entscheidenden Stellenwert ein, dass sich eine heteronomieästhetischeGrundierung der Moritz’schen Kunsttheorie aufweisen lässt. Diese tritt hervor,wenn man den Fokus darauf richtet, wie Ethik und Ästhetik zueinander insVerhältnis gesetzt werden: Moritz verpflichtet die autonome Kunst nicht einfachauf moralische Normen oder soziale Funktionen, modelliert aber den genialenKünstler als Praktiker, als ›Hand-Werker‹, dessen künstlerische Produktivität immerschon einem ›guten Leben‹ zuarbeitet. Der Aufsatz demonstriert, wie Moritz ineinem eigenwilligen Begriffsspiel mit dem Schönen und dem Guten ›Nachahmung‹neu entwirft als auf Moralität zusteuernde ästhetische Praxis. Diese praxeologischeGrundlage der Argumentation wirft zusätzlich ein neues Licht auf Moritz’ Rezeptionneuplatonistischer Philosopheme. Karl Philipp Moritz’s »Über die bildende Nachahmung des Schönen« (1788) is regarded asone of the key texts of autonomous aesthetics from the late 18th century. This article doesnot challenge this classification. Instead, it argues that Moritz’s metaphysics of art is foundedupon ethical practices. These practices are so essential to his conception, that one can show thatit is also based on heteronomous aesthetics. This aspect of his argument emerges from how herelates ethics to aesthetics. Moritz does not simply reduce autonomous art to moral norms orsocial functions. Instead he portrays the ingenious artist as an artisan (›Hand-Werker‹) whoseaesthetic productivity serves a ›good life‹. This article therefore demonstrates how Moritz playswith the concepts of the beauty and the good in order to remodel mimesis as an aesthetic practicethat significantly contributes to morality. Finally, by emphasising this praxeological foundationof Moritz’s argument, one can also reconsider his reception of Neo-Platonism "


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