I doubt that it is really wise to rely on the help from the people who are not specialists in it. I had a similar task and I need to confess that I asked the writers from "Marvelous Essay" to help with that. The result was even better than I have expected.
Answer:
railway cottages" are small workers' houses, originally built by railway companies for their employees (most likely in Victorian times). They tend to be near railway stations (but not in them) and railway lines, not surprisingly, and may even have a street address such as "3 Railway Cottages". They will all have been sold off on the private market, in most cases a long time ago, or bought up as social housing by local governments, so anyone may now live in them.
Explanation:
Part A: Line 6
Alliteration is the repetition of the same sound at the beginning of a group of words. Line 6 is "<em>Late spring sky,</em> Ms. Marcus says, <em>Almost summer sky.</em>" The /s/ sound is repeated fives times at the beginning of the words in this line of poetry.
Part B: It sounds soothing and peaceful.
The /s/ sound is a soothing and peaceful sound. Even the words soothing and peaceful have the /s/ sound. It creates a soothing a peaceful mood just like the long days at the end of spring and beginning of summer.
