WILDLIFE RESTORATION AND CONSERVATION 
 
magnesium. This series illustrates the great rapidity with which 
an alloy of such composition disintegrates. The first picture reveals 
a large piece of alloy in the lower esophagus. In the second picture, 
taken 13 minutes later, the alloy is situated at the entrance of the 
proventriculus and is already considerably disintegrated. A fairly 
large fragment of alloy is clearly separated from the main mass and 
several small granules of lead are also free. The next picture, taken 
58 minutes after feeding, exhibits the entire mass of lead alloy dis- 
integrated into small granules scattered throughout the gizzard. 
Small grains of alloy are plainly visible in two lobes of the intestine,

demonstrating that the alloy is being eliminated within 1 hour after 
feeding. 
The next two sets of lantern slides depict the complete disintegra- 
tion and elimination of alloy no. 17. The first picture, taken 1 hour 
after feeding, discloses the several large pieces of lead alloy still 
entire in the gizzard. In X-rays taken 24 hours later, complete dis- 
appearance of the original masses of alloy is evident. A very small 
amount of disintegrated lead is visible in the gizzard, but all the 
lead that has passed into the intestine has been completely eliminated 
from the birds. The third X-ray, taken after 3 days, shows no trace 
of lead anywhere in the duck. 
There are two ways in which the magnesium-lead alloy could pos- 
sibly be used as a basis for bird shot that will not cause lead poison- 
ing in waterfowl. Since shot made of this allow and used without 
any surface treatment would disintegrate rapidly in water, the 
residue mixing with the mud would not be eaten by waterfowl. The 
rate at which the shot would disintegrate in natural waters can 
easily be regulated by the amount of magnesium present. If the 
rate were made rather slow, some shot would at times be eaten. 
The ingestion of such shot would be entirely harmless because the 
grinding action of the gizzard on the highly disintegrable alloy 
would quickly eliminate the poisonous lead. It is possible to balance 
the ingredients of this shot so that it will slowly disintegrate in 
water and remain hard in flesh. It has not yet been possible to 
prevent the alloy from beconing granular in flesh during cooking 
and therefore less easily removable from cooked flesh than the pres- 
ent lead shot. It cannot be stated without more experience in utiliz- 
ing perfectly round shot whether or not this character is seriously 
objectionable. 
A second method of utilizing magnesium-lead alloy for bird shot, 
which might be considered even more satisfactory, has also been 
devised. This method requires putting an outer shell of such metal 
as copper over the surface of a core of magnesium-lead alloy. Shot 
constructed in this manner would act in all respects like shot now 
in use, except that it would not produce lead poisoning when eaten 
by waterfowl. Such shot would not disintegrate in water, but would 
accumulate as do present shot. They would remain perfectly hard 
in cooked flesh, as do present shot. Grinding off of the surface 
coating by the gizzard would be entirely harmless. As soon as the 
surface coating was worn through in any one place, the interior of 
the shot would immediately become soft. Gizzard action would then 
quickly pulverize the shot and the lead would pass from the gizzard 
as in the case of uncoated shot. The only objection, apparently, to 
the practical use of coated shot is that technical operations in its 
 
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