Dec. 1845.] 319 



while soft to have been penetrated by myriads of animalcule ; then dried 

 and baked into a solid mass, imprisoning and destroying the animals, 

 and forming a very porous soil, which, on subsequent exposure to water, 

 strongly impregnated with lime, received so much of the latter as to fill up 

 many of the pores when the water came to be dried up. 



Analysis. 1. The existence of roots, stems, or of any other fibrous matter 

 was sought for in vain in this specimen, and the magnet separates from it. 

 only minute quantities of magnetic oxide of iron. 



2. Fifty grains placed in a syphon-shaped drying tube in which it was ex- 

 posed to a heat of 212° for thirty minutes, and over which, during the whole 

 time, a current of perfectly dry air, amounting in all to 200 cubic inches was 

 passed, lost by this treatment 2.1 grains or 4.2 per cent. 



3. One hundred grains of the soil were boiled for ten minutes in four or 

 five ounces of distilled water, then filtered and washed. The insoluble resi- 

 duum, separated and dried, weighed 93.5 grains, and is of a reddish grey, 

 slightly varying in colour from the original soil. Deducting 4.2 from the 

 loss, the part soluble in boiling water is 2.3 per cent. To the clear solution 

 nitrate of silver imparted a slight milkiness, indicating the presence of chlo- 

 rine. Chloride of barium, producing no turbidness, implied the absence of 

 soluble sulphates. Oxalate of ammonia, gave evidence of a salt of lime so- 

 luble in boiling water. Phosphate of soda and ammonia gave no evidence of 

 magnesia, and ferrocyanide of potassium, none of iron. The liquid slowly 

 evaporated to dryness, left a residuum, which in the bottom of the porcelain 

 basin separated into a yellowish ring of crenic acid, giving the usual impres- 

 sion, first of acidity and then of astringency to the taste, and a central portion 

 of white crenate or carbonate of lime. 



4. Another portion of one hundred grains was exposed in a platinum cruci- 

 ble to a dull red heat over a lamp, by which it lost 8.65 grains, showing the 

 insoluble organic matter to be 2.15 per cent. The same portion afterwards 

 exposed for fifteen minutes to a nearly white heat lost in addition 5.3 grains, 

 and became of a light brick red colour. 



5. A third portion of one hundred grains finely pulverized was placed in 

 a green glass flask. An ounce of distilled water was poured over it, and an 

 open-mouthed tube containing chlorhydric acid was inserted, the mouth closed 

 with a cork traversed by a small glass tube surmounted by a tube containing 

 chloride of calcium. The whole being carefully counterpoised, the acid was 

 by degrees decanted and allowed to act on the soil. Heat was cautiously 

 applied near the close of the operation, bringing the liquid at length to gentle 

 ebullition, but taking care that no pure steam entered the chloride tube. On 

 cooling the apparatus, the air was allowed to pass through a second chloride 

 tube attached to the first, thus avoiding the hygrometric moisture of the air. 

 When the whole apparatus had become cool, heat was again applied and the 

 boiling and cooling repeated with the same precautions, until, on re-weighin°-, 

 no loss was found to occur between one boiling and another. The final loss 

 of carbonic acid was thus ascertained to be 5.55 per cent. 



6. Having withdrawn the cork from the flask, more chlorhydric acid was 

 added, and the boiling continued until every thing soluble had been taken up. 



39 



