Calcareous earth

Kalkentartuugt/. calcareous degeneration. Kalkerde, /. lime, calcium oxide calcareous earth. 

William Lewis stated m 1759 that the ash of bones and horn resembles chalk and the earth of the shells of sea-fishes. .. in being easily soluble m nitrous [nitric], marine, and vegetable acids, and not in the vitriolic." The only difference he was able to observe between the calcareous earth from shells and the bone ash was that the latter is not changeable by fire into Lime How strongly soever the earth of Bones and Horns be calcined, it continues insipid and gives no manifest impregnation to water (39). 

These considerations led me to conclude, that the relation between fixed air and alkaline substance, was somewhat similar to the relation between these and acids that as the calcareous earths and alkalis attract acids strongly, and can be saturated with them, so they also attract fixed air, and are, in their ordinary state, saturated with it and, when we mix an acid with an alkali, or with an absorbent earth, that the air is then set at liberty, and breaks out with violence because the alkaline body attracts it more weakly than it does the acid, and because the acid and air cannot both be joined to the same body at the same time. ... 

Henry Cavendish, in an investigation of the water of Rathbone Place in 1767, speaks of using as much fixed alcali, as was equivalent to 46 0 grains of calcarous earth, ue. which would saturate as much acid. ... 

Mineral alkali Calcareous earth Volatile alkali... 

Simple earthy rLime r Calcareous earth, lime... 

Lome Sulphate of Lime 4 Calcareous earth Selenite, gypsum Calcareous vitriol... 

Vitriolic acid to calcareous earth 110 Nitrous acid to vegetable alkali 215... 

It would not suffice to have decomposed gypsum, to have demonstrated separately the mixts that compose it, to have demonstrated that it was formed by the union of vitriolic acid with a calcareous earth, in a word that gypsum was nothing other than selenite it would still be necessary to take the materials nature employed, recompose a new gypsum which would produce the same effects, which would give the same phenomena. ... 

Following Black, Anderson held that pure limestone was made up of calcareous earth united with fixed air. In his words, calcareous earth was a general term denoting all those substances that consist of the matter which lime may be made, in whatever state it may be found - whether alone - or mixed with other substances, that prevent it from being reduced to powder after calcination. 33 For reasons of simplicity, he often used lime synonymously with calcareous earth. 34 Lime, as he explained, existed in three states. First, mild calcareous earth was limestone in its pre-calcined state. Second, Caustic calcareous earth was exactly synonymous with quicklime, in its strict and philosophical acceptation. 35 Finally, Effete calcareous earth was the hardened cement that formed from the quicklime which meant that it was a post-calcination form of limestone. As Anderson explained it Lime is no sooner slaked, than it immediately begins to absorb its air, and return to its former mild state or, in other words, it becomes effete, in which state it possesses the same chemical qualities, in every respect, as limestone. 36... 

These different states were based on Black s 1756 article in Essays and Reviews. To help his reader, Anderson offered his own nine variety arrangement of mild calcareous earth (since the caustic and effete were not stable).37 For each variety, he took care to note two classification characters purity and hardness. Purity referred to the percentage of mild calcareous earth contained in the stones, something that could be visually inferred from the stone s transparency. Hardness referred to how much the stone had been able to crystallize - a process in which saline substances, when dissolved in water, and put into proper circumstances for that purpose, separate from the water, and shoot into regular figures, which assume different forms, and are more or less transparent according to the different nature of the salt, as nitre, alum, c. 38 After setting out this classification, Anderson then proceeded to explain how chemistry could be used to find and assay calcareous minerals. 

Limestone Calcareous earth (pure and impure) that has formed crystals but which also contains sand... 

Table 2 in the Appendix gives a chart that contains the different types of earths accepted by Cullen, Black, and Walker. As Anderson stated Absorbent earths are all those that unite with acids, of which there are several varieties calcareous earths being one of these Anderson, Agriculture, 575. 

Furthermore, through the transformation of the sour tartar, it becomes calcareous earth and when distilled with sulfuric acid, it becomes the acrid Spirit of Vinegar. 

The Chinefe are faid, by Sir G. Staunton, to purify the water of fome muddy rivers or canals, by ftirring them with a hollow-cane full of fmall holes, in the tube of which are enclofed fome pieces of alum. And the bakers in London aflert, that one ufe of alum is to clear the New River water, and thus to render their bread whiter. Where any volatile alkali is mixed wdth water, as often happens from the liable dung and other ordure of populous towns, it will be converted to vitriolic ammoniac by a foiution of alum and calcareous earth may be converted into gypfum, and fubfide along with the earth of the alum. See Clafs II. I. 6. 16. ... 

IV, Water, river-water, fpring-water, calcareous earth. 

Inteftinal abforption is increafed by aftringent vegetables, as rhubarb, galls and by earthy falts, as alum and by argillaceous and calcareous earth. 

Thofe things which chemically deftroy acrimony, as calcareous earth, foap, tin, alkalies, in cardialgia, or which prevent... 

The importance of micro-organisms in the transformations taking place in the soil is evident from the following experiment of Miintz and Coudon, who have shown that if dried blood is added to a slightly calcareous earth, which is then sterilized at 120°, its inoculation with soil bacteria causes the appearance of considerable quantities of ammonia ... 

Air which has thus served the purpose of animal respiration is no longer common air, it approaches to the nature of fixed air [air containing CO2 and not Oj] in as much as it is capable of combining with lime-water and precipitating the lime from it, in the form of a calcareous earth but it differs from fixed air. 

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