March 29, 1918] 



SCIENCE 



309 



National Physical Laboratory, has continued 

 the series of tests for the committee on hard- 

 ness tests, with special reference to the effects 

 of variations of load and speed on rate of wear. 

 A series of wear ringrs of varying widths has 

 been made from material supplied by Sir Rob- 

 ert Hadiield, who has also undertaken their 

 hardening. Another holder for these rings has 

 been constructed of a form which will consider- 

 ably facilitate regrinding. A series of speci- 

 mens has been prepared and the tests are now 

 in hand. The work was delayed for some 

 mouths owing to some of the apparatus being 

 required for war work. In addition to the 

 grant of £100 made by the institution, a sum 

 of £100 has been received from the Depart- 

 ment of Scientific and Industrial Research, 

 Sir Robert Hadfield has placed in the hands of 

 the institution a sum of £200 to be awarded as 

 a prize or prizes for the description of new and 

 accurate methods of determining the hardness 

 of metals, especially those of a high degree of 

 hardness, but the council regret that as yet 

 few such descriptions have been received. 



The work of the committee on wire ropes, to 

 which a grant of £450 was made by the coun- 

 cil, has been much delayed by war work and 

 the prolonged illness of the chairman. Never- 

 theless a design for a testing machine has 

 been approved in principle for giving a some- 

 what wider range of tests than was originally 

 contemplated, in the direction of providing 

 for more bends both simple and reverse, and 

 also for bends in planes at right angles. The 

 choice of a site for its erection has been de- 

 ferred. 



In connection with the offer of a gift of £500 

 from Mr. Richard Williamson in aid of engi- 

 neering research, a number of suggestions for 

 subjects were received. The one which the 

 council selected was on the best form and ma- 

 terial for pistons and piston-rings, especially 

 for internal combustion engines, and they are 

 awaiting the approval of the Department of 

 Scientific Research through which Mr. Wil- 

 liamson's offer was transmitted. 



A PREHISTORIC PUEBLO INDIAN RUIN 



The American Museum of Natural His- 

 tory, in the summer of 1916, entered upon the 



largest single piece of scientific excavation 

 ever undertaken in the United States. This 

 was the systematic excavation and reparation 

 of one of the finest and best preserved ex- 

 amples of prehistoric Pueblo architecture in 

 the Southwest. The ruin is located in the 

 Animas Valley in northwestern New Mexico, 

 a few miles below the Colorado boundary 

 and directly across the river from the town 

 of Aztec, and is popularly, though inac- 

 curately, called the " Aztec Ruin." It is the 

 property of Mr. H. D. Abrams, of Aztec, who 

 has given the Museum a concession to clear 

 out and investigate the entire ruin. The 

 funds for carrying on the work have been 

 contributed by Messrs. Archer M. Hunting- 

 ton and J. P. Morgan. 



The '' Aztec Ruin " was once a typical 

 pueblo, or great fortified house and village, 

 comparable in the number of people sheltered 

 to the modern American apartment house, but 

 differing from it in that the principle of the 

 pueblo was close communal cooperation. The 

 buildings were so joined as to enclose three 

 sides of a rectangular court whose fourth side 

 was protected by a low, outcovering wall. 

 Only one entrance led through the outer wall 

 into the pueblo, which was, therefore easily 

 defended. The three buildings, rising sheer 

 from the ground on the outside, with very 

 small windows, rose within the court by reced- 

 ing steps, each a story high. Interior stair- 

 ways were not in use, access being gained to 

 upper levels by movable ladders. As a mili- 

 tary contrivance, this plan could hardly have 

 been improved upon, since an enemy would be 

 forced to make not one, but a series of attacks, 

 to get possession of the building. 



Although the work of investigation has as 

 yet been only partially comi)leted, the features 

 of the ruin itself, and the surprising finds 

 which have been made within the crumbling 

 walls, have proved of sufficient importance to 

 surpass the most sanguine expectations of the 

 investigators. Necklaces of shell and tur- 

 quoise, agate knives, pottery vessels of varied 

 form and ornamentation, cotton cloth and 

 woven sandals are among the gems of pre- 

 historic Pueblo art which have recently been 



