Page 65 - Loss of the VOC Retourschip Batavia, Western Australia, 1629

PROJECTILES Round solid shot
7 6
8
C ::I
60 70
80 90
100 110 120 130 140 150 160
Shot diameter in mm
Figure33. HistogramoftheironshotdiametersforalltheshotrecovccedfromtheBtJlavja.
A large collection of solid iron shot was found at the stem of the ship, lying up against the transom and, possi- bly, pan of the stem shot-locker. The shot were removed from the site and, following registration, the diameter of each shot was measured. In all, the diameters of 1425 projectiles were measured; by plotting a histogram of the diameters (Fig. 33), an indication of the main shot sizes was obtained, with peaks at 82 mm, 100 mm, 113.5 mm and 143 mm. Witsen (1671):501, gives a table (Table l) for weight of shot in pont(Amsterdam) against radius in duim x 100. By plotting the weight against radius cubed, a straight line is produced. Thedensity of the iron of the shot was 0.239 pont/duim' or 6.93 grams/cm' (using the con- stants 1 Amsterdam duim = 25.73 mm and 1 Amsterdam pont = 493.73 grams) and was determined from the slope of the line. This value is reasonably close to the value for grey cast iron of 7.03 grms/cm'. Given these values, the shot would therefore weigh 4.05,7.35, 10.75 and 21.04 pont respectively. The actual class of gun would be reck- oned from the height of the bore of the gun, which would be larger than the diameter of the shot, by the windage. Witsen (1671) gives another table (TableIl) for this, which indicates that the shot represent projectiles for 5 pom guns (bore diameter 90 mm), 8 pom guns (bore diameter 103 mm), 12 pont guns (bore diameter 116 mm) and 24 pom guns (bore diameter 148 mm). It is interesting to note that the shot diameter histograms do not show any marked
skew,this mayindicatethattheshotwerenotgauged.Ifthe shot were gauged, in other words passed through a ring to test if they were above a certain diameter, one would expect a skew in the plot, as all shot above a certain diameter would be rejected. This does not seem to be the casehere. Two other items which will be discussed below, are of relevance. These are the tally-stick BAT 4497 and the shot-gauge BAT 3336.
It can be seen from the histogram of the shot that there is a maximum at 82 mm corresponding to 4 pom, the upper limit of that peak corresponds to 5 pOm. The peak at 100 mm corresponds to a shot of7 pont with an upper limit for that peak at about 108 mm for a shot of 9 pont. The peak at 113.5 mm corresponds toashotof 11 pontwith an upper limit for that peak at 118 mm giving ashot of 12pont. The 11+ shot-gauge has a diameter of 113 mm, so the peak is reasonably close. Finally, the peak at 142 mm corresponds to a shotof21 pont with an upper limit for thatpeakatabout 146 mm corresponding to a shot of 23 pom. It should be noted that all these calculations were made using the Baravia tally-stick. This corresponds with the four differ- ent bore sizes noted on the bronze and iron guns, therefore we can see that the two smallest-class guns were iron, the third class was both bronze and iron, and the largest class was bronze. Van Dam (1701) records that the V.O.C. re- solved in 1604 that ships should be armed with guns firing 24,18,9 and 3.5 Ib balls,andby 1671 the guns were24,18, 8 and 4 Ib (Staple, 1927), thus to some extent the Batavia findings contradict these records.
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