#22 - Global Reference, Must Be True

[Administrator]

Complete Question Explanation
(See the complete passage discussion here: lsat/viewtopic.php?t=10866)

The correct answer choice is (B)

While the answer to this Global Reference question cannot be prephrased, the correct answer choice will be the only one that features a question we can answer by referring to the information contained in the passage.

Answer choice (A): The passage discusses the differences between contemporary glassmaking and glassmaking techniques used in medieval times and, not between the windowpane manufacturing techniques of medieval times and those of the 17th century.

Answer choice (B): This is the correct answer choice. The author discusses the difference in glassmaking techniques to help explain why some older windows are thicker toward the bottom (lines 46-57).

Answer choice (C): The author does not discuss the use of windows before medieval times, so this choice fails the Fact Test and cannot be the right answer to this Must Be True question.

Answer choice (D): Germanium oxide glass is mentioned in the third paragraph, to exemplify the fact that even a more easily flowing glass would take trillions of years to achieve any noticeable sagging, but the author does not mention whether such glass was ever used in medieval stained glass.

Answer choice (E): The author mentions that some impurities in medieval glass could have affected the viscosity and speed of the glass’ flow, but the passage provides no explanation of how medieval stained glass came to have those impurities.

[elizabethanne45]

Hi!

Question about a tiny detail. In the fourth paragraph, it says "until the 19th century, the only way to make window glass. . ." However, the answer choice (B) specifically references 19th century glass. Doesn't the word "until" imply that in the 19th century, glass making techniques changed? And, if so, the method described in the fourth paragraph would not be the 19th century method, but rather the method preceding the 19th century.

Please help to clarify! Thanks!

[Zach Marino]

Great question! I think it's important to realize here that the passage doesn't say the method that was used up until the 19th century suddenly stopped being used. Perhaps yes, the implication is that around the 19th century methods began to change, but I think it's a safe assumption that the switch didn't happen overnight and the method described may still have been in use into the 19th century. It's just not necessarily "the only" way any longer as the passage states. I hope this helps a bit!

[falconbridge]

I don't understand why E is incorrect. E states "How did there come to be impurities in medieval stained glass?"

Well, the passage states: "Until the nineteenth century, the only way to make window glass was to blow molten glass into a large globe and then flatten it into a disk. Whirling the disk introduced ripples and thickened the edges."

So since the beginning of window-making until the 19th century (which surely includes medieval times) the ONLY way to make window glass was via the process described above which introduced RIPPLES in the glass. Are ripples not impurities??

What am I missing here??

Falcon

[Paul Marsh]

Hey falconbridge! You said:

So since the beginning of window-making until the 19th century (which surely includes medieval times) the ONLY way to make window glass was via the process described above which introduced RIPPLES in the glass. Are ripples not impurities??

That's an interesting line of thought. But the passage never provides any support for the idea that ripples are impurities; that's an assumption on your part. And though I know next to nothing about glass-blowing (although I went to Venice once and they're all about it over there! Definitely check it out if you're ever in town), a quick Google search just now tells me that ripples in glass are actually a texture, not an impurity.

Cool idea though! But remember not to make assumptions in RC, just take what the passage gives you.

Hope that helps!