302 ANNUAL OF SCIENTIFIC DISCOVERY. 



umn of peat three feet square contains some specimen of ancient work- 

 manship. Mr. John Lubbock, of England, in a recent number of 

 the British Natural History Review, gives a detailed account of the 

 results of the investigations of Danish archaeologists. In a recent visit 

 by him to these ancient Danish dust heaps, many interesting speci- 

 mens of animal remains, shells, bones, etc., were collected. Of human 

 implements, they discovered flint axes, saws, chisels, etc., and small 

 pieces of coarse pottery, etc. Numerous human skeletons were found 

 in tumuli. The skulls were round, resembling those of the Laps. 

 Mr. Lubbock considers that the country must have been inhabited 

 several thousand years before the Christian era. He adds, no flint 

 implements have yet been found in Denmark resembling those occur- 

 ring in the drift near Abbeville and Amiens. Not only does the dif- 

 ference in workmanship, but also the absence of any trace of the 

 elephant and rhinoceros with the human remains in Denmark, and 

 their well-attested presence in France in the same strata with the 

 flint implements, tend to prove the greater antiquity of the latter. 



NATURAL DISSEMINATION OF GOLD. 



Mr. Eckfeldt, the Principal Assayer of the United States Mint at 

 Philadelphia, has lately made several interesting examinations tend- 

 ing to show the very wide distribution of gold. Passing over the 

 evidence respecting its presence in various galenas, in metallic lead, 

 copper, silver, antimony, etc., we cite the following, perhaps the most 

 curious result of all. Underneath the paved city of Philadelphia 

 there lies a deposit of clay, whose area, by a probable estimate, would 

 measure over three miles square, enabling us to figure out the con- 

 venient sum of ten square miles. The average depth is believed to 

 be not less than fifteen feet. The inquiry was started whether gold 

 was diffused in this earthy bed. From a central locality, which might 

 afford a fair assay for the whole, the cellar of the new market-house 

 in Market Street, near Eleventh Street, we dug out some of the clay 

 at a depth of fourteen feet, where it could not have been an artificial 

 deposit. The weight of one hundred and thirty grammes was dried 

 and duly treated, and yielded one-eighth of a milligramme of gold, 

 a very decided quantity on a fine assay balance. 



It was afterwards ascertained that the clay, in its natural moisture, 

 loses about fifteen per cent, by drying. So that, as it lies in the 

 ground, the clay contains one part gold in 1,224,000. This experi- 

 ment was repeated upon clay taken from a brickyard in the suburbs 

 of the city, with nearly the same result. 



In order to calculate with some accuracy the value of this body of 

 wealth, we cut out blocks of the clay, and found that, on an average, 

 a cubic foot, as it lies in the ground, weighs one hundred and twenty 

 pounds, as near as may be, mating the specific gravity 1.92. The 

 assay gives seven-tenths of a grain, say three cents' worth of gold, to 

 the cubic foot. Assuming the data already given, we get four thou- 

 sand one hundred and eighty millions of cubic feet of clay under our 

 streets and houses, in which securely lies one hundred and twenty-six 

 millions of dollars. And if, as is pretty certain, the corporate limits 

 of the city would afford eight times this bulk of clay, we have more 



