MUNIZ—MC GEE] RUDENESS OF TECHNIQUE 61 
PROCEDURE OF THE OPERATORS 
Some idea as to the technique of Peruvian trephining may be gained 
from a study of the procedure of the operators, as indicated by the 
character and sequence of steps in the better revealed operations. 
There are many indications that the operators were (1) inexpert in 
manipulation, (2) ignorant of physiology, (3) skilless in diagnosis aud 
treatment, and (4) regardless of the gravity of the operations performed. 
As already noted, there was a sequence in refinement of the bone cut- 
ting, running from the extravagant quadrangular button with eight 
projecting kerfs exemplified by cranium 1, and the still more barbarous 
slashing shown in cranium 5, to the relatively refined circular incision 
of cranium 8. Yet there is nothing to indicate that the sequence means 
anything more than a simple transition from the more clumsy to the 
less. There is scarcely a specimen, not modified by reparative growth, 
that does not display more or less extended kerf terminals and exten- 
sive scratches produced by the slipping of the tool; and the apertures 
display an irregularity of form attesting unfamiliarity either with geo- 
metric proportion in general or with the production of geometric figures 
by means of the facilities and under the conditions represented by the 
work. Most of the operations were evidently performed in random 
fashion without definite plan, by rule of thumb or by no rule at all. 
There was apparently no uniformity in the orientation of the quadran- 
gular operations save that of convenience in operating, and in several 
cases (e. g.,in the later operation in cranium 7, in cranium 8, and in the 
latest operation in cranium 18) the outline of the cutting was mani- 
festly determined by the attitude in which the subject was placed. In 
some of the more refined operations the incising blade was apparently 
held in such manner as to produce a tapering button and beveled mar- 
gin, yet most of the rectilinear and some of the curvilinear kerfs indicate 
that the tool was variously inclined, either through pure clumsiness and 
inattention, as in the outlying incision in cranium 1,in which (apparently 
by reason in part of interference with the integument) the tool was 
inclined at such an angle to the tangent as to require the cutting of bone 
to nearly twice the normal thickness of the skull, or by effort to keep 
the hand (and tool) out of the way of vision, as in cranium 8. So, too, 
when the bony surface was irregular or protuberant the tool was per- 
mitted to diverge, regardless of the originai direction, as in crania 4 
and 16. In short, there is nothing to indicate definite plan or deft 
execution in any of the operations. 
The extravagant incision and violent elevation characterizing many 
of the operations necessarily rendered the artificial lesions much more 
extensive and dangerous than necessary, aad the frequency with which 
this needless danger was incurred indicates that the operators had 
little if any notion of the physiologic processes involved in resistance, 
recovery, and reparation. In several cases, too, the cutting was care- 
lessly carried entirely through the bony tables so extensively as to 
