According to the Puritans, at what time did the Sabbath start and end? In college, many of my Presbyterian brothers wouldn't study on Sunday, seeing that as a violation of the Christian Sabbath.  But I heard that at least one of them, if he had a test on Monday morning, would wait until midnight Sunday night, and only then study for the test for a few hours before going to sleep.

The strict use of midnight in my brother's Sabbath observance has led me to wonder about the timing of the Sabbath in Puritan sabbatarianism more broadly.  So, I'd like to know – at what time did the Sabbath start and end for the Puritans?  I'm open to responses from both English and American Puritans, up to the 18th century.  If there isn't agreement, then I'd like an overview of common positions.
Puritans hold several different views regarding the exact timing of the Sabbath.  Perhaps the most widespread view is that the Christian Sabbath begins on Saturday at sunset and continues until sunset on Sunday.  

New England Puritan Thomas Shepard argues from Old Testament precedent for the evening-to-evening Sabbath:


  If, therefore, the Sabbath began at evening from Adam's time in innocency till Nehemiah's time, and from Nehemiah's time till Christ's time, why should any think but that where the Jewish Sabbath, the last day of the week, doth end, there the Christian Sabbath, the first day of the week, begins?1 


He clearly understands this to be a 24-hour period, saying that those at high latitudes, when the sun does not go down for weeks in the summer, are to measure the Sabbath day "by the circling sun round about them."1

Sunday night

Some Puritans maintained restrictions into Sunday night.  The Church of England in the early 17th century saw the Sabbath as ending Sunday evening, but Puritans like Nicholas Bownde opposed them on this point:


  Almost all bishops allowed for the use of lawful recreations after evening prayer [on the Lord's day]; a liberty that Bownde and other precisionists found abhorrent and contrary to scripture.


In the 17th century, Murray Rothbard writes, "the New England Sabbath began rigorously at sunset Saturday evening and continued through Sunday night,"2 and, similarly, Jonathan Edwards "preached often and sadly against 'Sabbath evening dissipations and mirth-making.'"3  In response, some derisively said that "New England Christians had improved [God's] law by setting apart a day and a half,"3 rather than just a single day.  But to be fair, at least some of these Puritans argued for a Sunday morning to Monday morning Sabbath, as described by Joseph Clark:


  The Puritans did not all commence their Sabbath on Saturday evening.  Mr. W. Perkins, in his "Cases of Conscience," [...] argues strongly in favor of beginning the Christian Sabbath "in the morning and so to continue till the next morning."4


Thomas Vincent takes this approach and specifies midnight as the beginning of the day, but requires preparation during the prior evening:


  In the evening before [...] we ought to begin to prepare for the Sabbath; but the Sabbath itself doth not begin until the evening is spent, and midnight thereof over, and the morning after twelve of the clock beginneth.5 


Daytime Sabbath

Finally, 17th century Puritan John Owen takes a different approach.  He recognizes that this question is "a matter of controversy" but does not consider it of "great importance."  He rejects the 24-hour (evening to evening) view, instead understanding that the Christian Sabbath lasts as long as the daylight:


  The day of labor is from the removal of darkness and the night, by the light of the sun, until the return of them again; which [...] seems to be the just measure of our day of rest.6


Summary

We've seen that the Puritans take several approaches to the question of the time of the Sabbath, as follows:


Saturday evening to Sunday evening
Saturday evening to Sunday night
Sunday morning to Monday morning


including, specifically, midnight Sunday to midnight Monday

Sunday morning to Sunday evening


It's thus not a matter of settled opinion.



References:


Shepard, Works, v3, 252
Rothbard, Conceived in Liberty, Volume 1, Chapter 20, 168
Earle, The Sabbath in Puritan New England, 256–57
Clark, in The Congregational Quarterly, v1, 275
Vincent, Explicatory Catechism, Question 58.6
Owen, A Treatise on the Sabbath, 214–16