Can you find the seven differences in the reflected (right-side) picture?
Engraving credit: John Tenniel
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"That's the effect of living backwards," the Queen said kindly: "it always makes one a little giddy at first--"
The right one on the left picture has no buttons.
Her socks lose their stripes on the right hand side.
The right guy on the right is NOT looking (with his eyes) on the polar opposite of what he was like on the left side.
There is an extra dot on her arm.
The claws in the middle are different.
Alice's shadow is different in both pictures.
One of the thing's hats has a different thing on top.
Hover to spoil them.
(click to enlarge)
Warning: lots of freehand
Written Differences: (R-L on R image)
1. Stripes on the girls socks
2. Her Elbow doesn't have that little shading
3. The buttons are missing on the guy on the right (I had initially counted each of his buttons as their own difference)
4. Signature thingy on top of his head (guy on the right)
5. Rock? Shading? under the umbrella handle (yes at first it looks like an axe/pick, but if you look closely you'll see that it's an umbrella)
6+7. are the other 2 buttons (see #3)
The actual other 2, which I noticed after @NL628 posted their answer:
6. Guy on right is looking in the other direction
Girls shadow is different (lighter)
Missing buttons on Tweedledum's belly.
Some odd symbol on the tree just above Tweedledum's head.
The umbrella handle's shadow has disappeared.
No stripes on Alice's foreground leg.
Tweedledum is looking at Tweedledee instead of at Alice.
Missing spot on Alice's elbow.
Alice lost her shadow.