ANTHROPOLOGY: T. MICHELSON 
297 
he may ride up in the head-gust, with the constraining device thrown off, 
to a height of some 4/ and then, with the device working, need drop 
only about / in the rear-gust. In this manner he can gain the amount 
3 J in altitude during each period. To avoid interference the successive 
maxima of the gusts should be at least 30 seconds apart for this machine. 
1 G. H. Bryan, Stability in Aviation, Macmillan, 1910; L. Bairstow, Technical Report of 
the Advisory Committee for Aeronautics, London, 1912-13; J. C. Hunsaker, these Pro- 
ceedings, 2, 278 (1916). 
2 A general lecture by Glazebrook, Aeronautical Journal, 272-301, July, 1914, should be 
cited, 
TERMS OF RELATIONSHIP AND SOCIAL ORGANIZATION 
By Truman Michelson 
BUREAU OF AMERICAN ETHNOLOGY. WASHINGTON 
Received by the Academy, April 17, 1916 
Some years ago Kroeber undertook to show that terms of relationship 
are Hnguistic and psychological phenomena.^ Recently Rivers has at- 
tempted to overthrow this view completely, and holds that they are 
sociological phenomena, and consequently that it is entirely possible to 
infer marriage customs and social organization from these terms.^ 
Lowie lately has to a certain extent followed Rivers; he has not fol- 
lowed the latter's survival-theories,^ and it is doubtful if many American 
ethnologists will do so.^ 
In this paper I wish to develop Kroeber's thesis from a different angle, 
and also to make a point on my own account. Long ago Morgan saw 
that for the most part the terms of relationships are identical in all 
Algonquian languages with phonetic changes, and consequently for the 
greater part must go back to the original parent language.^ Now in- 
sofar as this is the case, to this extent terms of relationship are Hnguistic 
phenomena. For example, the Fox are organized in exogamic gentes 
with descent in the male line, and the Plains Cree have no gentile 
organization at all, yet have at least seventeen terms of relationship in 
common Y/ith the Fox. Again the Delaware who are organized in exo- 
gamic clans with descent in the female line have some terms of rela- 
tionship in common with both the Fox and Cree. Similarly the Shawnee 
who have an entirely different organization from any of the above men- 
tioned Algonquian tribes,^ nevertheless have many terms in common with 
Plains Cree and Fox, and some with Delaware. Accordingly it is ob- 
vious that social organization is not the sole factor in terms of relation- 
ship. It may be objected that though Plains Cree and Fox possess 
