Clay Balls Research Articles

Formation of Clay Balls

Spherical masses of clay, "clay balls," are produced under certain conditions by the action of water, and, as such, have been found fossilized. In some cases, accretion seems to be the chief factor in their formation; in others, a wearing away of the projecting parts. In arroyo development the balls are formed by the latter method.

Certain Dusts as Agents for the Protection of Stored Seeds from Insect Infestation

Common white edible beans are protected from later attack by the common bean Weevil (Bruchus obtectus) when mixed in proper proportions With ground burned lime (CaO), hydrated lime Ca (OH)2 calcium chloride CaCl2, calcium sulfate CaSO4, dolomite, Highland Clay, Bond D Clay and Milltown Ball Clay No. 9. The protection which is afforded by these materials is most marked in the case of Milltown Ball Clay No. 9, and seems not to be connected with atmospheric moisture or chemical state of the dust materials. The protective ability of these materials appears to be correlated with the degree to which they exhibit a colloidal character-the more colloidal the more effective, the less collodial the less effective. This physical character seems to operate through preventing the larva of the bean weevil from obtaining sufficient foothold upon the surface of the bean seed to drill its way into the bean. Milltown Ball Clay No. 9, which is the most colloidal of all the dust materials worked with, appears to afford protection to wheat and shelled corn from later attack by the angoumois grain moth(Sitotroga cerealella). This clay apparently also has an insect reducing power when not in direct contact with the immature stages of the insects themselves. This insect infestation reducing power appears both in the case of the bean weevil and the angoumois grain moth.

In Support of Gardner's Theory of the Origin of Certain Concretions

In an article in the Journal of Geology, Gardner has maintained that certain concretions are formed in supersaturated or overloaded water carrying fine clay particles. He believes that the particles are pressed together and are gathered in lumps just as the finely disseminated particles of butter are gathered together in churning and that these particles grow by accretion and gain their spherical form by being rolled along the bottom. He bases his opinion on observations of aggregations of mud balls in the bed of a stream after a flood in the Rio Chaco region of the San Juan Basin, New Mexico. In the summer of 1921 the writer observed similar phenomena in the bed of the North Fork of the Red River, Beckham County, Oklahoma. As a result of a series of severe rains, this river, which is usually an insignificant stream flowing in sand-choked channels, had been flowing bank full. After the flood had subsided the writer observed on one of the sandy flats in the river bed a remarkable collection of clay aggregations similar to those described by Gardner. They consisted both of clay balls and cylinders, the former being much more numerous. The balls varied from less than an inch to about six inches in diameter. The cylinders were from four to six inches in diameter and a foot or more in length. Both balls and cylinders were composed of fine clay, with a small amount of sand and gravel in them or imbedded in the outer portion. The cylinders were apparently the result of two balls becoming stuck together and being rolled along the bottom, as several cases were observed showing the steps in this process. The considerable

V.—An Ancient Glacial Shore

In a cutting of the Seacombe Branch of the Wirral Railway at the present moment is to be seen a deposit which cannot be other than a glacial shore. It is about 18 inches thick, covered by a bed of Boulder-clay some 8 feet thick, and has been exposed by the cutting for a distance of 16 chains running south-east and north-west, to the south-east of the point of intersection of the Railway with Poulton Road. The rise is 16 feet in this distance at a regular up-grade towards Poultou Road, and the average level about 60 feet above O.D. Transversely to the Railway it is about level, and over the whole of the area—1056 feet by 30 feet=3520 superficial yards—the deposit occurred and was excavated by the steam navvy. The bed is composed of pretty clean sand with some small gravel, and is crowded with shell fragmentsinall stages of decay. It is precisely like a modern beachinconstitution, extent and slope, but what renders the fact more certain is the great quantity of clay balls or boulders mixed with the sand. These balls are covered over their surface with small gravel, shells and sand, picked up as they rolled about on the beach, just like the mud balls we find on the shore at Crosby at the present day. On being cut into with a knife these clay balls are seen to be formed of ordinary compact brown Boulder-clay, and they are pretty hard. The contractor, Mr. Davies, who is much interested in the geology of the cutting, tells me that these clay balls are found all over the area in great profusion, and as far as I tested the bed, which I did in at least half-a-dozen places, I found the statement correct. He also informed me that the bed is underlain by silt, but it has not been tested more than a few feet deep. I picked up and brought away about twenty clay balls varyinginsize from 3 inches down to ¾ inch diameter, some of them being spherical and others ellipsoidal inform.

On the Occurrence of Nodules (called Petrified Potatoes) found on the Shores of Lough Neagh in Ireland

The author stated that these peculiar nodules seem to be limited in their occurrence to the space between high and low water on the margin of Lough Neagh. Their average size is from two to three inches in diameter; they are irregularly spherical or suboval, with the surface occasionally indented. They are composed of a grey marlstone interspersed with black and green sand. They effervesce with acids. Extraneous fragments occasionally project from them and are half imbedded in their sides. On being broken they are found to be intersected with cracks, like septaria, probably the result of desiccation, and subsequently filled by crystalline carbonate of lime. The author explains the origin of these stones by referring to the analogous concretions of clay described by him many years ago, and occurring on the sea-shore at Lyme Regis. These latter are coprolitic, containing within them undigested scales and bones of fishes; but the Lough Neagh stones, although only containing fragments of stone, are, like these marine Bezoars of Lyme, formed by the rolling action of the waves of the lake on balls of clay, which gather up any extraneous substance that may come within their adhesive contact. They have been subsequently hardened by exposure to the drying action of sun and wind in summer, and afterwards have again undergone attrition by the waves when the waters of the lake have once more reached them, perhaps at the return of winter.