Mar.4] PROCEEDINGS. [1890.Beforeleavingthesemost ancienttools, it may be interesting to
comparethe first analysisgivenabovewithone made by Dr. Percy
of a supposed knifewhichwassaidto be found belowa statue of
RamesesII, and thirteen feet from the surface, viz. :—
Copper 97 'i 2
Arsenic ... ... 2-29
Tin ... ... ... 0-24
Iron ... ... ... o-43ioo-o8
Thedateof the knife wasprobablylong anteriorto that of the
statue.
Themetal of these tools is said to be rather soft,andat first
sightit would appear improbablethat such small impuritiescould
do much for hardening copper, andmakingit available for cutting
purposes; but Professor Roberts-Austen,whom I asked aboutthe
matter,writes," without questioneithertwo per cent, of tin or three
per cent, of arsenic wouldhavegreatinfluencein hardening copper,
and even such small quantities as two-tenths per cent, of either
elementwouldhavea very sensibleeffect." He thinks it probable
that the tools werehardenedby hammering, andaddsthat " they
may have beenoriginallymuchharderthantheyappearto be now,
as alloysof copperundergomolecularchangeby time and exposure."
As these toolsare supposed to date backto about 2500 B.C.,a period
whenthe majority of tools werestillmade of flint, thereis ample
timefor any change thatmightoccur.
Toolsof the Eighteenth Dynasty.
Mr. Petrie kindlygaveme similar boringsof some of the tools
which he had foundat Gurob, and which belongto the eighteenth
dynasty,about 1200 B.C. Thefollowinganalyseswereobtained:—
Smallhatchet. Largehatchet.
Copper ... 89-59 90^09
Tin ... ... 667 7-29
Arsenic ... 0-95 0'23
Antimony. ... trace trace
Iron ... 0-54 —9775 97 60
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