Here is a question about this article: By 1874, Bell's initial work on the harmonic telegraph had entered a formative stage, with progress made both at his new Boston "laboratory" (a rented facility) and at his family home in Canada a big success.[N 14] While working that summer in Brantford, Bell experimented with a "phonautograph", a pen-like machine that could draw shapes of sound waves on smoked glass by tracing their vibrations. Bell thought it might be possible to generate undulating electrical currents that corresponded to sound waves. Bell also thought that multiple metal reeds tuned to different frequencies like a harp would be able to convert the undulating currents back into sound. But he had no working model to demonstrate the feasibility of these ideas.
What is the answer to this question: On what material did the phonautograph operate?
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So... smoked glass

Here is a question about this article: New York City traces its roots to its 1624 founding as a trading post by colonists of the Dutch Republic and was named New Amsterdam in 1626. The city and its surroundings came under English control in 1664. New York served as the capital of the United States from 1785 until 1790. It has been the country's largest city since 1790. The Statue of Liberty greeted millions of immigrants as they came to the Americas by ship in the late 19th and early 20th centuries and is a globally recognized symbol of the United States and its democracy.
What is the answer to this question: What nation founded New Amsterdam?
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So... the Dutch Republic

Here is a question about this article: In temperate softwoods there often is a marked difference between latewood and earlywood. The latewood will be denser than that formed early in the season. When examined under a microscope the cells of dense latewood are seen to be very thick-walled and with very small cell cavities, while those formed first in the season have thin walls and large cell cavities. The strength is in the walls, not the cavities. Hence the greater the proportion of latewood the greater the density and strength. In choosing a piece of pine where strength or stiffness is the important consideration, the principal thing to observe is the comparative amounts of earlywood and latewood. The width of ring is not nearly so important as the proportion and nature of the latewood in the ring.
What is the answer to this question: Does strength come from the walls or cavities of wood cells?
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So...
walls