Sulfate was a trace constituent of Archean seawater.

In the low-oxygen Archean world (>2400 million years ago), seawater sulfate concentrations were much lower than today, yet open questions frustrate the translation of modern measurements of sulfur isotope fractionations into estimates of Archean seawater sulfate concentrations. In the water column of Lake Matano, Indonesia, a low-sulfate analog for the Archean ocean, we find large (>20 per mil) sulfur isotope fractionations between sulfate and sulfide, but the underlying sediment sulfides preserve a muted range of δ(34)S values. Using models informed by sulfur cycling in Lake Matano, we infer Archean seawater sulfate concentrations of less than 2.5 micromolar. At these low concentrations, marine sulfate residence times were likely 10(3) to 10(4) years, and sulfate scarcity would have shaped early global biogeochemical cycles, possibly restricting biological productivity in Archean oceans.

Three centuries of Eastern European and Altai lead emissions recorded in a Belukha ice core.

Human activities have significantly altered atmospheric Pb concentrations and thus, its geochemical cycle, for thousands of years. Whereas historical Pb emissions from Western Europe, North America, and Asia are well documented, there is no equivalent data for Eastern Europe. Here, we present ice-core Pb concentrations for the period 1680-1995 from Belukha glacier in the Siberian Altai, assumed to be representative of emissions in Eastern Europe and the Altai. Pb concentrations and (207)Pb/(206)Pb ratios were strongly enhanced during the period 1935-1995 due to the use of Pb additives in Russian gasoline mined in the Rudny Altai. Comparable to Western Europe and North America, Eastern European Pb emissions peaked in the 1970s. However, the subsequent downward trend in Eastern Europe was mainly caused by the economic crisis in the U.S.S.R. and not by a phase-out of leaded gasoline. Pb concentrations in the period 1680-1935, preceding the era of intensified industrialization in Russia, reflect the history of local emissions from Rudny Altai mining and related metallurgical processing primarily for the production of Russian coins. During this time, Altai ore Pb contributed about 40% of the regional atmospheric Pb.

Locality and circulation in the Habsburg empire: disputing the Carlsbad medical salt, 1763-1784.

By looking at the fierce debates in the city of Carlsbad in Bohemia around the fabrication of medical salt by a local doctor, David Becher, from 1763 to 1784, the paper examines the interactions between different spheres or levels of circulation of knowledge in the Habsburg Empire. The dispute crystallized around the definition of the product, about its medical qualities and its relation with the water of the local mineral spring. The city's inhabitants contested the vision of the medical experts, fearing that the extraction of the medical salt from the spring water and its sale outside the town would have a negative effect on the number of visitors to the spa. Their vision implied a more or less 'popularized' form of alchemical thinking as it identified the mineral water with the extracted 'salt', conceived as the 'essence' of the water, produced by evaporation. The Carlsbad salt dispute highlights the complex interactions among the different networks in which knowledge circulated through the Habsburg Empire in the eighteenth century. The different actors relied on specific networks with different logics of discourse and different modes of circulation. In each case the relation between the local, the regional and the imperial had to be negotiated. The paper thus sketches out the different geographies of knowledge in the Habsburg Empire but also its localization in and around Carlsbad.

[Léon Monsel and his solution]. / Léon Monsel et sa solution.

Léon Monsel was born on March 13, 1816 in Gironde. He did training courses in chemist's first near of home and then in Paris. He also studied pharmacy in Pharmacy School of Paris where he succeeded on August 12, 1840 and he entered army. He remained in it until his retirement in 1874. He died at Nancy on April 15, 1878. Monsel is overall well known by his publications about coagulation power of ferric sub-sulfate from which he described three preparation ways. Current publications are exclusively foreigner. They point out advantages and disadvantages of Monsel's solution. It is used to day as hemostatic agent in minor surgical procedures such as biopsies in genecology, dermatology, proctology and O.R.L. Besides when he was stationed in Roma he studied Acqua Acetosa (acid salty gaseous water) of this town and later when he was stationed in Bordeaux, he took out a patent about manufacturing varnish from metallic resinates.

[General situation of the study on the toxicity of Cinnabaris].

Traditional Chinese medicine (TCM) experienced a gradual course in recognition of the toxicity of Cinnabaris from "nontoxic" to "toxic". The ancient doctors of TCM understood both the toxic property and the regularity of increasing toxicity of Cinnabaris. In long-term clinical practice they developed the methods of detoxification guiding the safe use of Cinnabaris. The toxicity of Cinnabaris is produced by mercury existed in it. Improper administration leading to an acute absorption or chronic accumulation was the main cause of clinical adverse effects. Kidney was the main poisoning target organ. On the other hand, improperly combinative application of Cinnabaris with other drugs of TCM or western medicine could increase the toxicity. Therefore, the crucial approach to avoid the poisoning is to use Cinnabaris properly.

Long-term changes of acidifying deposition in Finland (1973-2000).

The long-term changes of acidifying deposition in Finland during the period 1973-2000 were studied using bulk deposition data from 19 stations belonging to the national monitoring network. The regional-scale approach (southern, central and northern Finland) was used for trend assessment with respect to implementation of European sulphur (S) emission reduction amendments involving deposition changes prior to (1973-1985) and after (1986-2000) the agreements (S protocols in 1985 and 1994). There were no marked changes in sulphate deposition between the 1970s and 1980s and consistent trends in 1973-1985 were not observed. Deposition of nitrogen (N) compounds, particularly NO3-N, were increasing between the 1970s and 1980s. Deposition of base cations exhibited a slight decline throughout the 1970s and 1980s. Decrease of calcium and magnesium deposition without corresponding decrease in sulphate resulted in increased acidifying potential (AP) of deposition. Due to successful implementation of S (and N) emission reduction measures, sulphate deposition has decreased substantially (30% in northern and up to 60% in southern Finland) since the late 1980s. N deposition also decreased, but less than S deposition. Base cation deposition has also declined substantially, but this decline appeared to be leveling off during the 1990s, accounting for the decrease of AP in deposition. The observed deposition pattern is in agreement with the on-going biochemical recovery of acidified small Finnish lakes taking place since the early 1990s.