ARCHEOLOGY. 395 



the fragments of which are abundant in Florida, the Gulf States, and 

 on the Gila, connecting an extinct with an existing art; and espe- 

 cially those specimens frequently disinterred in the Mexican States 

 belonging to the era of Aztec or Toltecan civihzation. It is espe- 

 cially important to ascertain the antiquity of these by careful obser- 

 vation of the circumstances under which they are discovered, in order 

 not to confound ancient with modern utensils. 



To this class also belong those articles found under conditions 

 which connect archa3ology with geology, and which may be classed 

 as follows: 



1. The contents of shell beds of ancient date found on the sea- 

 coasts and bays, often deeply covered with soil and overgrown with 

 trees, among which, besides the shells themselves, are frequently im- 

 plements of stone, bones of fish, animals, and birds used for food. 

 The examination of these collections in Denmark and other countries 

 of northern Europe has led to the discovery of remains belonging to 

 a period when a people having no other implements than those of 

 stone occupied the coast prior to the settlement there of the present 

 race. It is possible that a similar investigation in America may take 

 us back to a very remote period in aboriginal history. 



2. Human remains, or implements of human manufacture, bones of 

 animals bearing the marks of tools or of subjection to fire, found in 

 caves beneath deposits of earth and more especially of stalagmites or 

 stony material formed by droppings from the roof. 



3. Spear and arrowheads, or other weapons and evidences of fire 

 discovered in connexion with bones of extinct animals, such as the 

 mammoth, fossil elephant, &c., among superficial deposits, such as 

 salt licks, &c. 



4. Implements of the same description found in deposits of sand 

 and gravel or other like material exposed in bluffs or steep banks, 

 such as have recently attracted the attention of European geologists. 



In all these cases the utmost care should be taken to ascertain with 

 absolute certainty the true relations of these objects. In the case of 

 the shell banks, the largest trees, Avhere any exist, should, if practi- 

 cable, be cut down and the annual rings counted. Next the depth 

 of the superincumbent deposit of earth should be measured and its 

 character noted, whether of gravel, sand, or decomposed vegetable 

 matter, as also whether it has been stratified by the action of water. 

 Next the thickness of the shell bed should be ascertained and the 

 height of its base above present high water mark, as also whether it 

 exhibits any marks of stratification. Finally, the face of the bed 

 having been uncovered, a thorough examination should be made, 

 commencing at the top and carefully preserving everything which 

 exhibits signs of human art, and noting the depth in the deposit at 

 which they were discovered. Specimens of each species of shell 

 should be collected, and all bones or fragments of them saved. Evi- 

 dences of fire having been used should be watched for and recorded. 



In the search of caverns the same system should be followed. First, 

 the floor should be inspected for any recent remains either of men or 

 animals; next, the superficial earth should be carefully removed over 



