Geographies of steam: mapping the entrepreneurial activities of steam engineers in France during the second half of the eighteenth century

Entrepreneurship played a crucial role in the development and diffusion of steam technology. To account for this, we need to map the entrepreneurial activities that helped spread steam technology across Europe and beyond. Because tracing this history’s contours requires attending to local contexts, strategies and uses along with large-scale trajectories, it makes sense to speak of historical ‘geographies’ rather than of steam technology’s historical ‘geography’. Speaking of geographies in the plural also refers to the recognition that places can simultaneously be located in multiple spatial situations, their geographical identities the product of historical work, negotiation and perspective. To illustrate these points, this essay begins by reflecting on what might be called the ‘spatial turn’ in the history of technology and the role of entrepreneurship in the spread of steam technology in France during the second half of the eighteenth century, which is the historical focus of this essay. It then discusses a small number of representative cases of entrepreneurial engagement with steam technology in France and concludes by considering what this tells us about the relationship between the French state and its regions and the impact of the French Revolution in this geographically complex history.     

Sampling and analysis of geothermal fluids

Sampling of geothermal fluids presents some problems not encountered when sampling surface and nonthermal ground waters. Specific collection techniques are required to obtain representative samples because of the elevated temperature and boiling of these fluids, the effect of exposing them to the atmosphere and cooling of the samples. Sample treatment during collection depends on the analytical method to be used. When sampling wet‐steam wells, both the liquid and the vapour fractions should be collected at the same fluid separation pressure. When sampling fumarole steam, maximum information is obtained if the total discharge is collected into a single container without separating the gas and the steam condensate fractions. Silica polymerization affects the solution pH. The only way to obtain reliable pH measurement of a water sample supersaturated with respect to amorphous silica is to measure it on site, before the onset of polymerization. This paper provides an outline of the geothermal sampling techniques and analytical methods currently in use in Iceland. Sampling of hot‐water and wet‐steam wells is described, as is sampling of hot springs, fumaroles and gas bubbling through hot‐spring waters. Detailed procedures are given for the analysis of total carbonate carbon and total sulphide sulphur in geothermal water and steam condensate samples.     

Preliminary assessment of a wreck in the Red River, Choctaw County, Oklahoma, USA

This paper reports the initial recording of an early riverboat wreck located in the Red River between Oklahoma and Texas. The wreck is probably the Caddo lost in 1842. The visible wreckage is described and the history of the Caddo is discussed. This is the earliest western rivers steamboat investigated by archaeologists to date.     

Archaeology of the Early 19th‐Century American Steamboat Phoenix

In September 1819, the passenger steamboat Phoenix caught fire on Lake Champlain and sank off of Colchester Shoal, Vermont, depositing a store of archaeological data on the design and use of early American steamers. The wreck is believed to be the earliest example of a steamboat that has yet been investigated archaeologically, and has been used as a case study for the early development of steam propulsion in North America.     

Hydrogeochemical dynamics affecting steam‐heated pools at El Chichón Crater (Chiapas – Mexico)

El Chichón is an active volcano located in the north‐western Chiapas, southern Mexico. The crater hosts a lake, a spring, named Soap Pool, emerging from the underlying volcanic aquifer and several mud pools/hot springs on the internal flanks of the crater which strongly interact with the current fumarolic system (steam‐heated pools). Some of these pools, the crater lake and a cold spring emerging from the 1982 pumice deposits, have been sampled and analysed. Water–volcanic gas interactions determine the heating (43–99°C) and acidification (pH 2–4) of the springs, mainly by H₂S oxidation. Significantly, in the study area, a significant NH₃ partial pressure has been also detected. Such a geochemically aggressive environment enhances alteration of the rock in situ and strongly increases the mineralization of the waters (and therefore their electrical conductivity). Two different mineralization systems were detected for the crater waters: the soap pool‐lake (Na⁺/Cl^? = 0.4, Na/Mg>10) and the crater mud pools (Na⁺/Cl^? > 10, Na/Mg < 4). A deep boiling, Na⁺‐K⁺‐Cl^?‐rich water reservoir generally influences the Soap Pool‐lake, while the mud pool is mainly dominated by water‐gas–rock interactions. In the latter case, conductivity of sampled water is directly proportional to the presence of reactive gases in solution. Therefore, chemical evolution proceeds through neutralization due to both rock alteration and bacterial oxidation of ammonium to nitrate. The chemical compositions show that El Chichón aqueous fluids, within the crater, interact with gases fed by a geothermal reservoir, without clear additions of deep magmatic fluids. This new geochemical dataset, together with previously published data, can be used as a base line with which to follow‐up the activity of this deadly volcano.     

The Western River Steamboat Heroine, 1832–1838, Oklahoma,USA: excavations,summary of finds,and history

This paper describes the excavation, discoveries relating to the hull, machinery, and artefacts, and the history of an early steamboat wreck discovered in the Red River between Oklahoma and Texas. The wreck has been identified as the side‐wheel steamer Heroine, a vessel in service on the Mississippi, Ohio, and other western rivers of North America during the 1830s. It is the earliest example of this famous type of vessel yet studied.     

近代长江流域行轮内港时空变迁研究(1898—1929年)——基于《<内河行轮章程>项下华洋轮船行驶 内港名录》的复原

1898年清廷颁布《内港行船章程》后,长江内河轮运骤兴,开放轮船行驶的内港日渐增多,截至1929年全流域有超过418处内港开放行轮,内河航运格局为之一变。长江流域开放行轮的内港在空间上集中于下游地区,中游也有较多分布,上游地区则十分稀少。行轮内港的开放在时间上则呈现出下游到上游、干流到支流两种趋势。近代行轮内港的时空变迁趋势反映了轮运这一新式交通在长江流域的发展情况。     

Admiral: a 19th‐century Tyne‐built paddle tug

This paper reports on the discovery in the Thames Estuary and the partial recovery and recording of the remains of a 19th‐century Tyne‐built paddle tug. The wreck is believed to be that of Admiral built in Newcastle in 1870 and sunk following a collision in the estuary in 1872. This unexpected discovery provided a rare opportunity to examine the archaeological assemblage of one these once‐familiar working vessels and revealed the continuities and innovations of a specific type of engine used on paddle tugs.     

基于屏幕跟踪的大学生在线旅游信息搜索行为研究

本文以大学生在线旅游信息搜索行为为研究对象,利用实验观察法（屏幕跟踪）,分析了在线旅游信息搜索行为特征及规律,并依据信息搜索行为理论,构建了大学生在线旅游信息搜索模式。研究发现,在规定情景任务的情境下,大学生在网络信息搜索中输入的关键词次数不高,且习惯于使用短语或具体景区的名称并加入限定词语进行搜索;该群体整体上偏好使用全文搜索工具进行信息搜索,且信息搜集量大;该群体对信息的关注度依次为“游”、“行”、“住”、“吃”、“购”,但对“娱”的关注几乎没有;研究还发现,关键词和搜索引擎的选择与其旅游经验和上网经验有正相关关系。