S. HOLTH: M.-N. KI. 
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The steelyard is of bronze, like all the medical instruments except 
one, which shall be mentioned below. The patina of some of the instru- 
ments is greenish, but on most of them of an even deep brownish black, 
with green dots in tiny hollows in the surface (some of these hollows 
can only be discovered under a magnifying glass). 
In both cases the patina is not altered by washing in water or alcohol, 
and it is of a kind which can only be produced by the work of centuries 
and which no falsifiers have succeeded in imitating however great their 
efforts. If a tiny chip is cut out of some instruments through the patina 
layer, the shining surface of the cut is somewhat yellowish red. A fresh sur- 
face of fracture which I saw by an unvolontary break of a sound (PI. II, 3) 
was greyish and granulary crystalline. Some instruments (Pl. I, 25—29, 
Ill, 13, 19, 20 and 23) must have been broken in antiquity as the granu- 
lary surface of the fractures are covered with the same kind of patina like 
the rest of the instruments. I have until now not been willing to sacrifice 
any of the instruments on a chemical analysis; according to Milne the 
bronze of Greco-Roman surgical instruments in cases analysed appeared 
a binary alloy of copper and tin with the alloy of tin nearly always 
about 7.5 9/, !. 
I will first speak about a Roman bronze steelyard which is drawn on 
Pl. I in siae X. ?/,. 
The steelyard consists of a quadrangular lever 34 cm. long, forming 
a balance with two unequal arms, provided with three crooked handles 
and with three different engraven scales of weight, probably one scale for 
each handle. The goods were probably placed in a dish hanging by cords 
attached near the end knob of the short arm. (See however foot note 
p. 7. The sliding weight was not found; in a Pompeian steelyard, which 
I have seen, the bronze sliding weight had the shape of a woman's head 
attached by a short chain, sliding on the long arm of the steelyard; this 
1 In connection with my lecture Professor J. Sebelien (Aas, Norway) gave some interest- 
ing information about the different composition of old bronzes. — ‘The thought struck 
me that our bronzes might have another alloy than the alloy mentioned by Milne, 
Professor Sebelien has been kind enough to submit to a quantitative analysis as many 
samples of my instruments as I could procure. I have taken samples with pinchers 
or file; the colour of the fresh surfaces is different, copper red, yellowish red, reddish 
yellow, and yellow; but in Pl. III, 19 it is grey and in 20 the broken surface resembles 
cast iron. The bronzes in these two latter instruments and in No. 21 contain much 
lead (13.44 9/o, 30.02 % and 6.85 0/5). No. 20 contains 10—12 9/9 of Zinc, Iron and 
Cobalt — mainly Cobalt. No. 4 is pure copper, No. 6 contains 92.94 9/9 copper and 
5.30 9/9 tin. The others contain copper from 74/9 to 85/5, tin in most of them from 
0.5 to 3.4 9/o, while the zinc alloy is great (between 11 9/9 and 2299). The detailed 
analyses by professor Sebelien will be found on the table p. 5. He will later publish 
a paper on the bronze question in the »Forhandlinger« or »Skrifter« of our Society. 
