Multi-strike cent?

[Robert]

On page 91 of the May 24 Coin World, they show a pic of a 1918 cent that was struck "at least 10" times. The cent's perimeter is essentially round and flat (that is, not too badly odd-shaped) and the multiple strikes are shown mostly in the truncation of the bust. His horizontal truncation line appears many times, working its way "north" so that it looks like Lincoln is some kind of West Point cadet with all his "stripes". In the strongest strike, Lincoln's head is intersected by the rim of the coin at 12 O'Clock. There is also a fainter image of Lincoln, slightly better centered and at 11 O'clock.

My question is this. Is it possible for a coin to be struck multiple times, with each strike moving "north", and yet still be "round"? Seems to me that if the coin moved "south" relative to the dies, it couldn't have stayed in the collar and would not therefore be flat.

If it stayed in the collar, wouldn't it become a brockage? Wouldn't it be bottlecap shaped (not flat) or otherwise irregular?

I'm not sure I buy their exlpanation.

[Bob P]

Robert,
I did not see that article, but I do have a little insight into muliple strikes. During a tour of the Philadelphia mint in the early 80's, I asked almost the same exact question. I had seen a quarter that was struck 5 times, yet remained perfectly round. The answer I got at the time was pretty basic, but after seeing the machinery work, I agreed with the man's reply. He stated that in the case of multiple struck coins that pretty much remained round, the coin may never leave the collar. After each strike, the ejection fingers are supposed to pop the coins out of the collar. If the finger is broken or misadjusted, it doesn't pop the coin out at all, but merely pushes it up a bit. As the coin settles back in the collar, it is easy to see how a little rotation may occur. It is struck again, but since it is still in the collar, and already struck (at least) once, then when the die comes down to do the next strike, the amount of pressure used to strike a normal blank planchet isn't appplied because most of the coins surface has already been struck. Only the higher portions receive a subsequent strike.
Since the coin is not stuck on the die, it wouldn't become bottle cap shaped. It is still a free moving coin. It wouldn't be a brockage because another planchet or coin is not in the collar, and therefore it cannot strike the coin causing the reverse image.
Ultimately, a couple of things need to go wrong before an error such as you mentioned happens. The ejector fingers are broken or misadjusted, AND on the other side of the machine, there are no planchets being fed into the collar. Until the coin is either finally ejected, or manually removed, it is possible for this to happen continuously....in the case of this coin, at least 10 times.

[Robert]

Bob, I can accept most of that explanation, except that the coin appears to have been struck further and further "north" while still in the collar.

How can the obverse die hit the coin 40% off center to the north but still make contact with the planchet AND still have the coin be "flat"? Seems to me the die would hit the collar before it hit the planchet if it was that far off-center.