Cite evidence from a primary and a secondary source and analyze how each develops its central ideas

Learning goal: Cite specific textual evidence to support an analysis of a primary source and a secondary source, determine the central ideas or information of each, provide an accurate summary that includes those central ideas, and analyze the relationship between the two sources when they treat the same topic.

Two invented sources about one topic. Both texts below were written for this lesson. The letter imitates the form of a primary source from the 1850s; the essay imitates the form of a modern secondary account. Neither is a real document. Daniel Marsh and his letter are fictional and are not intended to represent any historical person or document, the village and lock he describes are not real places, and every number inside the letter belongs to the letter-writer, not to the real Ohio canal system. What is real is the general setting: Ohio built state canals, among them the Ohio and Erie Canal, begun in 1825, which joined Lake Erie at Cleveland with the Ohio River at Portsmouth; boats on them were towed by animals walking a towpath; locks raised and lowered boats between levels; and railroads, as they spread, drew freight and passengers away from the canals. This lesson is about how to read, not about those events, so treat the two texts as practice material and check any historical claim against a real source before you repeat it.

Original fictional primary-style source — Letter from Daniel Marsh, lock tender, to his brother, 12 March 1854 (invented for this lesson).

Dear Samuel,

The ice went out of the canal on Tuesday and the first boats came down from the summit level on Thursday, so I am back at the gates from before daylight until the last boat passes, which some nights is near ten o'clock. You asked what a lock tender does. Mostly I wait, and then I hurry. A boat blows its horn a quarter mile off, the boy on the towpath slows the mules, and I have the lower gates open before the bow comes level with the chamber. I close the gates behind the boat, open the wickets in the upper gates, and the water comes in with a noise like a mill race. The boat rises about nine feet in the time it takes to say a long grace. Then the upper gates, and the mules lean into the line, and off she goes toward Akron. Twenty-two boats passed on Saturday. I keep a tally on a slate because the collector at the office wants the count, though he takes the tolls himself and I never touch the money.

The State pays me by the month, and the pay is the same as when I started three seasons ago. The railroad men who are grading the line east of the village are said to get more, and to get it in the winter too, when the canal is drained and I have nothing to do but mend gates and split wood. I do not know if what they say about the pay is true. I know that two of the boat captains who used to tie up here have sold their boats this spring, and that the grain from the Miller farm went out by wagon to the railhead last fall instead of by boat, because the buyer in Cleveland would not wait the extra week.

Mother should not worry. The work is steady while the water is in, and the house that comes with the lock is dry and has a good stove. Still, I have been asking whether the railroad will want men who understand water and gates, and the answer so far is no. If you hear of anything in the mills at Massillon, write to me. Tell Mother the peach tree by the lock house has buds on it.

Your brother, Daniel

Original secondary account — Working the Locks: Ohio's Canal Era in Decline (a short essay written for this lesson in the voice of a modern local historian; it is not a published work).

Ohio's canals were a public project. The state financed the Ohio and Erie Canal between Lake Erie and the Ohio River, begun in 1825, among others. The canals were shallow, slow and closed in winter, but a boat hauled by two mules at a walking pace could carry many times the load of a farm wagon, which made the canals attractive for heavy goods such as grain, flour, pork and salt.

The system depended on people whose names rarely appear in published histories: the boat captains, the boys who drove the animals on the towpath, the toll collectors and the lock tenders. A lock tender lived beside the lock, often in a house provided by the state, and was responsible for moving every boat through the chamber, day and night, for the whole season that the canal held water.

As railroads spread, the canals lost traffic to them, because railroads ran all year and did not have to wait for ice to melt. Workers felt this change before the state acknowledged it. A letter written in 1854 by Daniel Marsh, a lock tender on the Ohio and Erie Canal, records that two boat captains at his lock had sold their boats that spring and that a nearby farm had shipped its grain to a railhead by wagon rather than by canal. Marsh also notes that his monthly pay had not risen in three seasons while railroad workers were reported to earn more. His letter shows that canal workers understood the threat the railroad posed to their livelihoods and were already looking for other work.

The canals did not vanish overnight. Some sections carried freight for decades, and tolls were still being collected long after the railroads arrived. But the men and women who worked the water saw, in the empty tie-ups and the wagons rolling toward the railhead, the shape of what was coming.

What makes a source primary or secondary. A primary source is created by someone who took part in or witnessed the events: a letter, a diary, a toll ledger, a photograph or a speech made at the time, but also a memoir or a recorded interview in which a witness recalls the events years later. A secondary source analyzes, interprets or synthesizes evidence about the events, usually other people's evidence: a textbook chapter, a museum label, a historian's essay. Its author usually did not witness the events, but a witness who later writes a history from documents and other people's accounts is writing a secondary source for everything beyond his own testimony. The test is the source's relationship to the particular events and question, firsthand testimony against analysis or synthesis, not the age of the paper and not how soon after the events the source was made; a memoir written forty years on is primary evidence of what its author witnessed and remembered, and its distance from the events is a limit to weigh, not a change of category. Two conditions matter. First, a source is primary for the thing it witnesses and secondary for anything it merely reports: Daniel is a witness to his own gates and pay, but he only passes along what the railroad men "are said" to earn. Second, primary does not mean accurate. A letter can exaggerate, misremember or leave things out; it is close to the event, which is a different quality from being right about it.

Citing specific textual evidence. An analysis is a claim about what a source shows or how it works. Evidence is the particular words that support that claim. Specific means you can point to the sentence: quote it or paraphrase it closely and say where it comes from. Compare two attempts to support the claim that Daniel's work was demanding. Weak: "The letter says the job is hard." Strong: "Daniel writes that he is at the gates from before daylight until the last boat passes, which some nights is near ten o'clock, and that twenty-two boats passed on a single Saturday." The strong version names the words, and the words match the claim. A quotation that is accurate but irrelevant is not evidence for the claim in front of you, however impressive it sounds.

How content-area text develops. History texts develop their ideas in recognizable ways, and analyzing content-area-specific text development means saying what each part does for the idea, not just what it is about. A personal source usually develops by association: the writer moves from what he was asked, to what he saw, to what worries him. Daniel's letter goes from the lock routine, to pay, to the captains and the grain, to his search for other work. A secondary account usually develops from a general statement toward evidence and back to interpretation. The essay opens with the canal system, narrows to workers, narrows further to one letter, and then widens again to what the letter "shows." Tracing this movement is analyzing development.

Central ideas and an accurate summary. The central idea of a source is what its details add up to, and in a history text it is often not stated in a single sentence. Daniel never writes that the railroad threatens his job. He gives the pay that has not changed, the men who are said to earn more, the captains who sold their boats, the grain that went by wagon, and the railroad that does not want him. Put together, the central idea is that his steady work is being undercut by the railroad and he is beginning to look elsewhere. The essay's central idea is stated more directly: the decline of the canals was felt first by the people who worked them. An accurate summary includes those central ideas, keeps the source's own limits (Daniel does not know whether the railroad pay is true), and adds nothing the source does not contain. The most common error is to summarize what you think happened in history instead of what the source says. "Daniel lost his job when the canal closed" is not in the letter.

The relationship between a primary and a secondary source on the same topic. The essay uses the letter as evidence. Read the two side by side and three things become visible. First, the essay reports the letter accurately on the captains, the grain and the pay. Second, the essay adds context the letter cannot supply: when the canals were built, why railroads had an advantage, what happened later. Daniel could not know in March 1854 what the next decades would bring. Third, the essay stretches the letter. It places Daniel on the Ohio and Erie Canal, which the letter never names; boats leaving "toward Akron" make that a reasonable guess, but it is the historian's inference, not the letter's statement. Daniel describes his own lock; the essay says "canal workers understood the threat." One man's letter cannot establish what workers in general understood. It can support a claim about Daniel and suggest a question about others. Analyzing the relationship means saying which claims in the secondary source the primary source actually supports, which the secondary source brings from elsewhere, and where the secondary source goes beyond its evidence.

A fully worked model. Claim: the essay's statement that Daniel was "already looking for other work" is supported by the letter. Evidence: Daniel writes, "I have been asking whether the railroad will want men who understand water and gates," and asks Samuel, "If you hear of anything in the mills at Massillon, write to me." Reasoning: asking two different places about employment is looking for other work; the claim is about Daniel, and the letter is Daniel's own account, so the evidence is direct. Limit: the letter does not show that he left, or that other tenders did the same. The claim survives; a broader claim would not.

A misconception. Students often believe the secondary source is the answer and the primary source is the story. The reverse is closer to the truth in practice: the secondary source is a set of claims, and the primary source is one of the pieces of evidence that the claims must answer to. When they disagree, or when the secondary source says more than the primary source can bear, the reader's job is to notice, not to choose the more authoritative-looking text.

Worked citation: Claim: Daniel's information about railroad pay is second-hand. Evidence: "The railroad men who are grading the line east of the village are said to get more," and "I do not know if what they say about the pay is true." Reasoning: the phrases "are said" and "I do not know" mark the information as reported, so the letter is primary evidence that the rumor existed at his lock, not evidence that railroad pay was in fact higher. An analysis that cited the letter to prove railroad wages would be citing the wrong thing.

Worked central idea and summary: A student summary reads: "Daniel Marsh hated being a lock tender and quit to work on the railroad." Check each part against the letter. He calls the work steady and the house dry, so "hated" is unsupported. He asked whether the railroad would want him and "the answer so far is no," so "quit to work on the railroad" contradicts the source. An accurate summary: "In an invented 1854 letter, lock tender Daniel Marsh describes his season's work at the gates, notes that his pay has not risen in three seasons while railroad workers are said to earn more, reports that two captains have sold their boats and that a farm shipped its grain by wagon to the railhead, and asks his brother about work in the mills." Every clause can be traced to a sentence.

Worked relationship analysis: The essay states, "Workers felt this change before the state acknowledged it." The letter says nothing about what the state acknowledged. Half of the sentence (workers felt it) draws on the letter, and even that half generalizes from one worker; the other half comes from the historian's other knowledge, which the essay does not cite. Mark the sentence in three parts: supported for Daniel; not established for workers generally by this letter; not supported by this letter at all for the state. That is what analyzing the relationship between the sources produces, a map of where the secondary claims rest.

Evidence log (representation): Make a three-column table: the claim; the quoted or closely paraphrased evidence with the source and paragraph named; what the evidence does not show. Enter four claims: two sentences from the essay that rest on the letter, and two claims of your own about the letter. For each, mark whether the letter is primary evidence for the claim (Daniel witnessed it) or only secondary (Daniel reports what others said). Exchange logs with a partner and check that every entry can be found in the text.

Independent performance: Write a two-paragraph analysis. Paragraph one states the central idea of each source and gives an accurate one-sentence summary of each. Paragraph two analyzes the relationship between the two sources: one place where the essay reports the letter accurately, one where it adds context the letter lacks, and one where it goes beyond what the letter can support. Success criteria: every claim has a quoted or closely paraphrased citation with the source named; no summary sentence contains information absent from the source; the words primary and secondary are used with the reason they apply; and the analysis describes both texts as invented for this lesson, never as real records.