What is a lancet window?

A lancet window is a tall, narrow window with a pointed arch at its top. It acquired the "lancet" name from its resemblance to a lance. Instances of this architectural element are typical of Gothic church edifices of the earliest period.

Explanation:

answer; i believe the correct answer is (forms with no projecting parts that could break;

the correct answer for this question is:

it is system invented in 1872 that produced the first illusion of movement. basically it was a disk with a series of drawings around the edge, showing the same object in slightly different poses. when it was spun, it created the illusion of movement.

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