The territory of Massachusetts was included in the first charter of Virginia, granted in 1606, and in the charter of New England, granted in 1620.
In 1628 the council of Plymouth made a grant to the governor and company of Massachusetts Bay in New England, which was confirmed by the King, and a charter was granted in 1629, from which the following extracts:
***Nowe, Knowe Yee, that Wee *** have given and graunted ***all that parte of Newe England in America which lyes and extendes bewteene a greate River there comonlie called Monomack River, alias Merrimack River, and certen other River there, called Charles River, being in the Bottome of a certan bay there, comonlie called Massachusetts, alias Mattachusetts, alias Massachusetts Bay; and also all and singuler those Landes and Hereditaments whatsoever, lying within the Space of Three English Myles on the South Parte of the said River, called Charles River, or of any, or every Parte thereof; and also all and singuler the Landes and Hereditaments whatsover, lying and being within the space of three Englishe Myles to the southward of the Southernmost Parte of the said Baye, Called Massachusetts, alias Mattachusetts, alias Massachusetts Bay; and also, all those Landes and Hereditaments whatsoever, which lye and be within the Space of Three English Myles to the Northward of the saide River, called Monomack, alias Merrymack, or to the Northward of any and every parte thereof, and all Landes and Hereditaments whatsoever, lyeing within the Lymitts aforesaide, North and South, in Latitude and Bredth, and in Length and Longitude, of and within all the Bredth aforesaide, throughout the mayne Landes there, from the Atlantick and Westerne Sea and Ocean on the Easte Parte, to the South Sea on the West Parte;
***Provided alwayses, That if the said Landes *** were at the tyme of the graunting of the saide former Letter patents, dated the Third Day of November, in the Eighteenth Year of our said deare Fathers Raigne aforsaide, actuallie possessed of inhabitted by any other Christian Prince of State, or were within the Boundes, Lymyttes or Territories of that Southene Colony, then before graunted by our said late Father *** That then this present Graunt shall not extend to any such partes or parcell thereof, *** but as to those partes or parcells *** shal be vtterlie voyd, theis presents or any Thinge therein conteyned to the contrarie notwithstanding.
The charter of New England was surrendered to the King in 1635 ...
The charter of Massachusetts Bay, granted in 1629, was canceled by a judgement of the high court of chancery of England, June 18, 1684.
In 1686 Pemaquid (part of the present state of Maine) and its dependencies were annexed to the New England government.
In 1691 a new charter was granted to Massachusetts Bay, which included Plymouth Colony and the Provinces of Maine and Nova Scotia. The following are extracts from this charter:
***Wee doe *** will and Ordeyne that the Territories and Collynes comonly called or known by the Names of the Collony of the Massachusetts Bay and Collony of New Plymouth and Province of Main the Territorie called Accadia or Nova Scotia and all that tract of land lying betweene the said Territories of Nova Scotia and the said Province of Main be Erected Vnited and Incorporated *** into one reall Province by the Name of Our Province of the Massachusetts Bay in New England *** all that parte of New England in America lying and extending from the greate River comonly called Monomack als Merrimack on the northpart and from three Miles Northward of the said River to the Atlantick or Western Sea or Ocean on the South part and all the lands and Hereditaments whatsoever lying within the limits aforesaid and extending as farr as the Outermost Points or Promontories of Land called Cape Coad and Cape Mallabar North and South and in Latitude Breadth and in Length and Longitude of and within all the Breadth and Compass aforesaid throughout the Main Land there from the said Atlantick or Western Sea and Ocean on the East parte toward the South Sea or Westward as far as Our Collonyes of Rhode Island Connecticut and the Marragansett Countrey all alsoe all that part of porcon of Main Land beginning at the Entrance of Pescata way Harbor and soe to pass vpp the same into the River of Newickewannock and through the same into the furthest head thereof and from thence Northwestward till One Hundred and Twenty miles be finished and from Piscata way Harbor mouth aforesaid North-eastward along the Sea Coast to Sagedehock and from the Period of One Hundred and Twenty Miles aforesaid to crosse over Land to the One Hundred and Twenty Miles before reckoned vp into the Land from Piscataway harbour through Newickawannock River and alsoe the North halfe of the Isles and Shoales together with the Isles of Cappawock and Natuckett near Cape Cod aforesaid and alsoe [all] Lands and Hereditaments lying and being in the Countrey and Territory comonly called Accadia or Nova Scotia And all those Lands and Hereditaments lying and extending betweene the said Countrey or Territory of Nova Scotia and the said River of Sagadahock or any parte thereof And all Lands Grounds Places Soiles Woods and Wood grounds Havens Ports Rivers Waters and other Hereditaments and premisses whatsoever, lying within the said bounds and limitts aforesaid and every part and parcell thereof and alsoe all Islands and Isletts lying within ten Leagues directly opposite to the Main Land within the said bounds.
The present northern boundary of Massachusetts was first surveyed and marked in 1741... [New Hampshire]

The east-west part of the boundary between Massachusetts and Rhode Island is a part of the original southerly line of the territory granted by the council at Plymouth to Sir Henry Roswell and others in the third year of the reign of King Charles I and redefined in the charter granted to the colony of Massachusetts Bay in 1691. This line was for more than 200 years a matter of dispute that was in some respects the most remarkable boundary question with which this country has had to deal. Twice the question went to the Supreme Court of the United States, and in one of these suits Daniel Webster and Rufus Choate were employed as counsel for Massachusetts.
As early as 1642 the line between the two colonies was marked in part by Nathaniel Woodward and Solomon Saffrey, who set up on the plain of Wrentham a stake as the commencement of the line between Massachusetts Bay and Rhode Island. This stake Woodward and Saffrey thought marked a point 3 miles south of the Charles River ...
In 1710-11 commissioners appointed from Massachusetts and Rhode Island agreed upon the north line of Rhode Island, and their action was approved by the legislatures of both colonies. The agreement follows:
That the stake set up by Nathaniel Woodward and Solomon Saffrey, skilful, approved artists, in the year of our Lord one thousand six hundred and forty-two, and since that often renewed, in the latitude of forty-one degrees and fifty-five minutes, being three English miles distant southward from the southernmost part of the river called Charles River, agreeable to the letters-patents for the Massachusetts province, be accounted and allowed on both sides the commencement of the line between Massachusetts and the colony of Rhode Island...
In 1719 this line was run by commissioners appointed for the purpose, but subsequent investigation has shown that it was run very inaccurately...
The line between Massachusetts and the eastern part of Rhode Island was fixed by the commissioners in 1741. The colony of Rhode Island appealed from their decision to the King, but in 1746 he affirmed it by royal decree. In accordance with this decree the line was run in 1746 by commissioners of Rhode Island whose report may be found in the US Supreme Court record for the December term, 1852, pages 208-210.
In 1748 the Legislature of Rhode Island appointed commissioners to continue the line to the Connecticut corner, the Woodward and Saffrey stake being recognized as the place of beginning. Mass failed to appoint commissioners, where upon the Rhode Island commissioners proceeded to complete the running of the line. In their report they say with reference to the initial point of their survey:
That we, not being able to find any stake or other monument which we could imagine set up by Woodward and Saffrey, but considering that the place thereof was described in the agreement mentioned in our commission, by certain invariable marks, we did proceed as followeth, namely; We found a place where the Charles River formed a large current southerly which place is known to many by the name of Poppatolish Pond, which we took to be the southernmost part of said river, from the southernmost part of which we measured three English miles south, which three English miles did terminate upon a plain in a township called Wrentham.
From this time forward, repeated steps were taken by Rhode Island, by resolutions and by appointment of commissioners, to ascertain and run the line in connection with commissioners from Massachusetts. Commissioners from both colonies met more than once, but they failed to agree upon a boundary in place of that established under the agreements of 1711 and 1718. As a ground for these efforts Rhode Island alleged that a mistake had been made by her commissioners in commencing the line at the accepted position of the Woodward and Saffrey stake, which, as set on Wrentham Plain, at Burnt Swamp Corner, was considerably more than 3 miles south of the Charles River.
This controversy, however, embraced the entire line from Connecticut to the Atlantic Ocean. Massachusetts asserted that an encroachment has been made on her territory from Burnt Swamp Corner to the ocean by Rhode Island, who, on her part, claimed that the jurisdictional line of Massachusetts from that corner to the Connecticut line was, in its whole extent, upon the territory of Rhode Island. The legislatures of the respective States having failed after repeated efforts to adjust the controversy, Rhode Island in 1832, by a bill in equity, brought the subject of the northern boundary from Burnt Swamp Corner to the Connecticut line before the Supreme Court of the United States, which in 1846 decided that the jurisdictional line claimed by Massachusetts was the legal boundary of the two States between these points.
In this decision, the following declaration was made:
"For the security of rights, whether of states or individuals, long possession under claim of title is protected, and there is no controversy in which this great principle may be invoked with greater justice and propriety than in a case of disputed boundary".
While this suit was pending an attempt was made to settle the long controversy by an amicable adjustment of the whole line from the Connecticut corner to the ocean. Commissioners were appointed by both States in 1844 to ascertain and mark the true boundary from Pawtucket Falls (presumably near the present city of Pawtucket) south to Bullock Neck. In 1845 the same commissioners were authorized to ascertain the entire line from Burnt Swamp Corner to the Atlantic Ocean.
In 1846, the equity suit having been decided..., they were authorized "to erect suitable monuments at the prominent angles of the line, from the Atlantic Ocean to the northwest corner of Rhode Island, and at such other points on the line as may subserve the public convenience." A majority of the commissioners agreed upon a line and erected monuments in 1847.
The report of the joint commission was dated Boston, January 13, 1848. The line so agreed upon as a boundary between Burnt Swamp Corner and the northwest corner of Rhode Island was a straight line, varying a little from the irregular jurisdictional line established by the decision of the Supreme Court, and is described in the report of the commissioners as follows:

Begin at the northwest corner of Rhode Island, on Connecticut line, in latitude 42º00´29˜ north, and longitude 71?48´18˜ west of Greenwich, thence easterly in a straight line 21.512 miles to Burnt Swamp Corner, in Wrentham, being in latitude 42?01´08˜ and longitude 71?23´13˜....
Upon this line, 27 monuments were placed exclusive of that at Burnt Swamp Corner.
The General Assembly of Rhode Island, in May 1847, ratified and established the line from the ocean to the Connecticut line, "to take effect and become binding whenever the said agreement and boundary line should be ratified by the State of Massachusetts." The legislature of Massachusetts did not ratify the agreement and boundary line but proposed another joint commission, which was approved by Rhode Island. The attempt made by these commissioners to settle the line having failed, Massachusetts commenced a bill in equity before the Supreme Court of the United States for an adjudication of the boundary line from Burnt Swamp Corner to the Atlantic Ocean.
In 1860 both States agreed upon a conventional line and asked that a decree of the U. S. Supreme Court should confirm the same. The prayer was granted, and the line was thus finally established by a decree rendered December 16, 1861.
The Supreme Court decision made no reference to the line from Burnt swamp corner to the Connecticut line. In 1865 the Legislature of Massachusetts took action in regard to this portion of the line, as follows:
Resolved, That the boundary line between the state of Rhode Island and the Commonwealth of Massachusetts, from the line of the State of Connecticut to Burnt Swamp Corner, begins at the north west corner of the State of Rhode Island on the Connecticut line, in latitude 42?00´29˜ north, and longitude 74?48´18˜ [sic] west of Greenwich, and runs in a straight line 21 and 512/1000 miles to Burnt Swamp Corner, in Wrentham, being in latitude 42?1´8˜.60 and longitude 71?23´13˜.26. [later this coordinate {74?} was corrected].
This is the line agreed upon by commissioners and called the "line of 1848," which was ratified by Rhode Island when run but was rejected by Massachusetts.
As a result of the tardiness of Massachusetts in ratifying the line, Rhode Island rejected it on the ground that the then recent settlement of the eastern boundary by the decree of the Supreme Court had so changed the aspect of the controversy that she could not consent to the adoption of the line of 1848 as her northern boundary. Thus the northern boundary of Rhode Island was left in the condition prescribed by the Supreme Court decision of 1846.
In June 1880, the Legislature of Rhode Island passed a resolution to remove the monuments of the "line of 1848" and erect monuments on the jurisdictional line. In 1881 the Legislature of Massachusetts took like action. This jurisdictional line has the same termini as the line of 1848 but is a very irregular line, in places running north of a direct line and elsewhere falling south of it, the extreme variation being 529.3 feet north and 129 feet south. It is described as follows:
Beginning at a monument of dressed granite, marked "Mass." on the north, "R.I." on the south, and "Con." on the west sides, standing at the northwest corner of the State of Rhode Island, in latitude 42?00´29.45˜, longitude 71?48´18.07˜ west of Greenwich; thence running easterly in a straight line to a pile of stones on the western bank of Wallum pond at high-water mark; thence easterly in a straight line to the southwest corner of Uxbridge and the southeast corner of Douglas, to a monument of dressed stone, marked "D Nov. 9, 1829," on the northwest face and "U" on the east face, and "B" on the south face; thence running easterly in a straight line to a point formed by the intersection of the easterly line of Harris Avenue, so called, with the southerly line of Gaskill Street near the bridge of Waterford, and about fifteen rods easterly of the easterly bank of the Blackstone River; thence running easterly in a straight line to a monument of split stone granite about five feet above ground, having five faces, marked on the west face "M", on the northeast face "B", and on the south face "C"; thence easterly in a straight line to the stone monument now standing on Wrentham Plain at Burnt Swamp Corner, *** marked on two sides Mass. and the other two sides R.I.
The following statement concerning the east boundary of Rhode Island was made by the commissioners of 1897-98 for both States:
On March 1, 1862, a decree of the Supreme Court of the United States issued the previous year became effective, which changed the boundary line between the Commonwealth of Massachusetts and the State of Rhode Island. By this change the town of Pawtucket west of the Seven and Ten Mile rivers, a narrow strip of Seekonk between the middle of the above-named rivers and the line of highest water on the eastern banks, and the southwestern part of Seekonk, now East Providence, were annexed to Rhode Island, in exchange for territory in the vicinity of Fall River. The Legislature of Massachusetts anticipating this change, provided by chapter 187 of the acts of 1861, for the proper jurisdiction of the territory east of the new boundary, and the State of Rhode Island by a similar act, chapter 379 of the acts of 1861, provided for the jurisdiction of the new territory acquired west of this line.
On account of the imperfect marking of this line and the difficulty of defining the high-water line of rivers and ponds, which formed the State boundary, it was decided in 1897 to redefine the line and to substitute for indefinite high-water boundaries a series of straight lines as near as may be to the line established by the decree of 1861, which could be readily and permanently marked.
The general court of that year authorized the topographical survey commission, representing Massachusetts, to act in conjunction with a commission representing Rhode Island, in locating, defining, and marking the State boundary line, from "Burnt Swamp Corner" southerly to the sea.

A full report of the doings of these commissions was made in May 1899, and the general courts of both States promptly ratified their work by the passage of acts which contain a full description of the line.
The 1898 survey of the east boundary of Rhode Island was commenced at Burnt Swamp Corner, marked by a granite monument inscribed "Mass.-R.I 1861-1883; 1898," in lat 42?01´08.35˜ and long 71?22´54.51˜. The line thence runs S. 2´40˜ W. 8.65 miles, thence east and south by straight-line courses of irregular length to a point where it intersects the line of high water of the Atlantic Ocean, in lat 41?29´50.87˜, long 71?07´15.62˜, about 45.789 miles from the point of beginning. The termini of all the straight lines are marked by the old monuments where recovered or by new granite monuments 12 by 12 inches by 9-1/2 feet, suitably lettered and set 5-1/2 feet in the ground.

CONNECTICUT
In 1713, commissioners from the Province of Massachusetts Bay and colony of Connecticut adopted a line between Massachusetts and Connecticut. By this line the frontier towns of Woodstock, Suffield, Enfield, and Somers were given to Massachusetts. In 1749 the Legislature of Connecticut passed a resolution stating that inasmuch as the line had not been approved by the King and the two colonies had no legal right to transfer territory without the confirmation of the Crown, the contract was void, and these towns were again taken under the jurisdiction of Connecticut. Massachusetts appealed to the King, and the claims of Connecticut were fully established.
In 1791 Massachusetts and Connecticut appointed commissioners to establish the boundary between them, but the commissioners were unable to agree.
In 1803 commissioners were appointed to complete the line west of the Connecticut River, a compromise having been made concerning the line between the town of Southwick and the towns of Suffield and Granby (the cause of the disagreement of the former commissioners). The agreement was made as follows:
That the line should begin from a station 8 rods south of the southwest corner of West Springfield, and thence run west to the large ponds, and thence on said south line to the ancient southwest corner of Westfield and from thence on said south line to the ancient southwest corner of Westfield; and from thence northerly in the ancient west line of Westfield to the station in said west line made by commissioners in the year 1714, and from thence to the southwest corner of Granville.
The reason for this peculiar deviation from a straight boundary, known as the "Southwick Jog" is that, in adjusting errors in the boundary line between Connecticut and Massachusetts as previously run by compass, a long, narrow strip of land was given to Connecticut; the Southwick jog ceded to Massachusetts was intended to be an equivalent area...
In 1826 the line between Massachusetts and Connecticut east of the Connecticut River was run by commissioners appointed from each State, and 49 stone monuments were erected, marked "M" on the north side and "C" on the south.
The same commissioners surveyed and marked the line from the northeast corner of Connecticut to the northwest corner of Rhode Island, reporting as follows:
Beginning at the monument erected at the northeast corner of said State of Connecticut and running in a direct line to the ancient heap of stones on the north side of the turnpike leading from Hertford to Boston, through Thompson and Douglass, where we erected a monument, and thence running in a direct line to the northwest corner of the State of Rhode Island.
The present boundary between Massachusetts and Connecticut was fixed by a joint commission authorized by legislative acts of both States in 1905. The line as surveyed and marked was approved by Massachusetts in 1908 ... by Connecticut in 1913, and by the U. S. Congress October 3, 1914 .... Part of it is thus described:
Beginning at a granite monument at the northwest corner of the State of Rhode Island and marking the corner of Massachusetts, Rhode island, and Connecticut, in latitude 42?00´29.150˜ and longitude 71?47´58.778˜; [thence in a general northerly direction] to a granite monument at the northeast corner of the State of Connecticut, in latitude 42?01´24.807˜ and longitude 71?48´04.123˜ [these coordinates were later adjusted in the 1927 North American Datum].
From this corner, the boundary is approximately a straight line bearing 1? or 2? north of west to a point near the Connecticut River.
From a granite monument in lat 42?02´04.619˜, long 72?31´55.276˜, the line runs as follows: [in the following description, the latitudes and longitudes are omitted]

South ... and west, 11,309 feet to a granite monument about 620 feet south of Allen Street in Longmeadow ... thence south 3,238 feet to a granite monument 450 feet east of the main road from Thompsonville to Springfield,... ; thence north... 5,834 feet to a granite monument on the top of the bank, about 175 feet east of the easterly shore of the Connecticut River,...; thence in the same direction, 950 feet to the middle of said river; thence northerly along a line midway between the banks thereof, about 2,075 feet; thence ... 1,206 feet to a granite monument standing on the bank about 225 feet west of the westerly shore the river, ...; thence in the same direction 7,661 feet to a granite monument about 875 feet west of North Street, or Suffield Street, the middle road from Suffield to Springfield, ...; thence north west 8,966 feet to a granite monument on the easterly side of Halladay Avenue, or Front Street, the road from Suffield to Feeding Hills, ...; thence north ... west to a granite monument on the easterly side of West Street, the road from West Suffield to Westfield ...; thence south west 4,137 feet to a granite monument at the corner of Agawam and Southwick in Massachusetts and Suffield in Connecticut,...; thence south... west 132 feet to a granite monument, ... ; thence south west, 11,231 feet to a granite monument on the easterly shore of Congamond Lake, ...; thence in the same direction, 14.5 feet to the shore of the lake as it would be with the surface of the water at the elevation it was in 1803; thence southerly, by the easterly shore of the lake as it would be with the surface of the water at the aforesaid elevation to a point opposite a granite monument near the shore at the southerly end of the lake; thence south... west, about 25 feet to said monument, ...; thence in the same direction 1,632 feet to a granite monument at the southeasterly corner of the "Southwick Jog" ... thence south west 13,827 feet to a granite monument at the southwesterly corner of the "Southwick Jog", in ...; thence north east 14,261 feet to a granite monument known as the "Crank Monument", in latitude 42?02´12.399˜ and longitude 72?48´51.223˜.
From this corner the line runs on a general westerly course, bearing about 1? north of west, to
a large rock, marked 1803 on its southerly side, in Sage's Ravine, in latitude 42?03?02.214˜ and longitude 73?26´00.030˜; thence south 88?31´58˜ west 14,787 feet to a granite monument at the northwesterly corner of the State of Connecticut and marking the corner of Massachusetts, New York, and Connecticut, in latitude 42?02´58.427˜ and longitude 73?29´15.959˜.

NEW YORK
The boundary between Massachusetts and New York was from an early period a subject of controversy, New York claiming to the west bank of the Connecticut River, under the charters of 1664 and 1674 to the Duke of York, and Massachusetts claiming to the "South Sea", under the old charters. After many fruitless attempts at a settlement, the western boundary of Massachusetts was fixed in 1773 where it now meets New York territory. The Revolution soon following, the line was not run. In 1785 Congress appointed three commissioners to run the line, who performed that duty in 1787. The line was as follows:
Beginning at a monument erected in 1731 by commissioners from Connecticut and New York, distant from the Hudson River 20 miles, and running north 15?12´9˜ east 50 miles 41 chains and 79 links, to a red or black oak tree marked by said commissioners, which said line was run as the magnetic needle pointed in 1787.
The claims of Massachusetts to western land within the territory of the State of New York were finally settled December 16, 1786, by a joint commission of the two States. By this agreement Massachusetts surrendered the sovereignty of the whole disputed territory to New York and received in return the right of soil and preemption right of Indian purchase west of the meridian passing through the eight-second milestone of the Pennsylvania line ... except certain reservations upon the Niagara River. The title to a tract known as "The Boston Ten Towns," lying east of this meridian and previously granted to New York by Massachusetts, was confirmed....
On April 19, 1785, Massachusetts executed a deed transferring to the United States all title of Massachusetts to territory west of the present western boundary of New York.
In 1820 Maine, previously a part of Massachusetts, was admitted into the Union as an independent State.
In 1853 an area of about 1,010 acres in the southwest corner of Massachusetts, known as Boston Corners, was ceded to New York, and in 1855 the cession was confirmed by Congress.
The present boundary between Massachusetts and New York was thus described from resurveys by a joint commission in 1899: [most coordinates are omitted here]
Beginning at bound 1, a granite monument set in ledge on the side of a wooded mountain peak six hundred and nine feet east of Ryan Bush Road, in latitude 42?02´58.427˜ north of the equator, and longitude 73?29´15.959˜ west from Greenwich, and marking the northwest corner of Connecticut, a corner of the Commonwealth of Massachusetts, and a corner of the State of New York; then on an azimuth of 90?43´49˜, twenty-six hundred and twenty-four feet to bound 3, a granite monument set in ledge on the steep westerly slope of a wooded mountain ... at the southwest corner of Massachusetts, also in the eastern line of New York, and marking a corner of the towns of Mount Washington, in Massachusetts, and Ancram and Northeast, in New York; thence on an azimuth ... thirteen thousand six hundred and forty-nine feet to bound 9, a granite monument set in ledge on the westerly wooded slope of Alandar Mountain about a quarter mile west of its summit, ... at the corner of Mount Washington, in Massachusetts, and Copake, in New York; thence on an azimuth ... two hundred forty-nine thousand two hundred and forty-six feet, by the towns of Mount Washington, Egremont, Alford, West Stockbridge, Richmond, Hancock, and Williamstown, in Massachusetts, and Copake, Hillsdale, Austerlitz, Canaan, New Lebanon, Stephentown, Berlin, and Petersburg, in New York, to bound 112, a granite monument set in ledge and earth on an open easterly slope about seventy-five feet west of a private roadway ... at the northwest corner of Massachusetts, also in the east line of New York and in the south line of Vermont, and marking a corner in the boundaries of the towns of Williamstown, in Massachusetts, Petersburg, in New York and Pownal, in Vermont.
The term "azimuth" as used in this description is the angle which a line makes at its point of beginning with the true meridian, reckoning from the south around by the west.
This location of the line was approved by Massachusetts May 8, 1901, and by New York June 9, 1910 ....

VERMONT
By the terms of the charter of Massachusetts Bay, of 1629, that colony was granted all the lands
which lye, and be within the space of three English Myles to the Northward of the said River called Monomack alias Merrymack, or the Northward of any and every parte thereof.

Under this clause, Massachusetts Bay claimed that its jurisdiction extended to a line 3 miles north of the northernmost part of the Merrimack River, such jurisdiction would embrace a large part of New Hampshire and Vermont. New Hampshire contested this claim and after several years' controversy was more than sustained by a decision of the King in 1740... Massachusetts agreed to the independence of Vermont in 1781 [and was admitted to the Union as a State in 1791].
The south boundary of Vermont is part of the north boundary of Massachusetts, which was fixed by the King in council under date of August 5, 1740, and surveyed under the direction of Governor Belcher in 1741. It was resurveyed and re-marked by commissioners representing the two states between 1885 and 1898. This survey was commenced at the northwest corner of Massachusetts, at a monument consisting of a granite post 8 feet long and 14 inches square set nearly 5 feet in the ground. The faces toward the different States were marked "N.Y. 1898", "Mass. 1896" and "Vt. 1896". Its geographic position is lat 42?44¨44.7˜ N., long 73?15´54.13˜ W. (1927 N. A. D.). From this point the boundary is a nearly straight line, bearing about 2? south of east (true bearing), and runs 41 miles to the southeast corner of Vermont, which is a mark on the west bank of the Connecticut River.

NEW HAMPSHIRE
After the death of Capt. John Mason, in December 1635, the affairs of the colony [of New Hampshire] coming into bad condition, the colonists sought the protection of Massachusetts in 1641 and enjoyed it till 1675, when Robert Mason, a grandson of John Mason, obtained a royal decree, under which, in 1680, a colonial government was established. But no charter was given to the colony, and its government was continued only during the pleasure of the King. The commission or decree issued by the King in 1680 to John Cutt, of Portsmouth, names the following limits for the colony:
Province of New Hampshire, lying & Extending from three miles northward of the Merrimack River, or any part thereof to ye Province of Maine.
In the year 1690 the Province of New Hampshire was again taken under the jurisdiction of Massachusetts Bay, but in 1692 it was once more separated.
A controversy that arose between the Provinces of New Hampshire and Massachusetts Bay involved not only the boundary between New Hampshire and Maine but also that between New Hampshire and Massachusetts. The commissioners appointed by the two Provinces having been unable to agree, New Hampshire appealed to the King, who ordered that the boundaries should be settled by a board of commissioners appointed from the neighboring colonies. The board met at Hampton in 1737 and submitted a conditional decision to the King, who in 1740 declared in council
that the northern boundary of the province of Massachusetts be a similar curve line, pursuing the course of the Merrimack river, at three miles distance, on the north side thereof, beginning at the Atlantic Ocean, and ending at a point due north of Pautucket falls [now Lowell], and a straight line drawn from thence due west, till it meets with his Majesty's other Governments.
New Hampshire had claimed her southern boundary to be a line due west from a point on the sea 3 miles north of the mouth of the Merrimack River. Massachusetts had claimed all the territory within 3 miles north of any part of the Merrimack River. The King's decision gave to New Hampshire a strip of territory, more than 50 miles in length and varying in width, in excess of that which she claimed. This decree of the King was forwarded to Mr. Belcher, then governor of both the Provinces of New Hampshire and Massachusetts Bay, with instruction to apply to the respective assemblies to unite in making the necessary provisions for running and marking the line conformably to the said decree, and if either assembly refused, the other was to proceed ex parte. Massachusetts Bay declined to comply with this requisition. New Hampshire therefore proceeded alone to run and mark the line.
....
Under the King's decree of 1740, the Province of New Hampshire claimed jurisdiction as far west as the territory of Massachusetts and Connecticut extended, thus including the present State of Vermont. New York claimed all the country west of the Connecticut, under the charters of 1664 and 1674 to the Duke of York. A bitter controversy ensued...
The south boundary of New York as surveyed between 1885 and 1898 is marked by 50 large cut-granite monuments at irregular intervals. The initial point of this survey is the southwest corner of New York and southeast corner of Vermont, marked by a copper bolt in the top of a block of granite set in a mass of concrete 6 feet square, "at or near ordinary low-water line" on the west bank of the Connecticut River ....
From the State corner the line was run on a general course about 2-1/2? south of east (true bearing), measured distance of 57.84 miles to
the boundary pine monument, so-called, standing between the towns of Pelham, New Hampshire, and Dracut, Mass, in the pasture land owned by Zachariah Coburn, at a point where one George Mitchell, surveyor, marked a pitch pine tree, March 21, 1741, then supposed to be 3 miles due north of a place in the Merrimack River formerly called Pawtucket Falls, now Lowell.
....
From this point the boundary consists of a series of straight lines, approximately paralleling the Merrimack River and 3 miles distant therefrom.

Massachusetts is one of the very few States that has had her boundary lines adequately marked and by frequent inspection maintains the marks in good condition. In addition to the marking of her exterior lines the State has also had comprehensive surveys made of interior township boundaries. The lines and corners are controlled by an accurate system of triangulation; therefore if any number of marks were destroyed the exact positions of new ones to replace them could be readily ascertained from the triangulation data. The results of these surveys are published by the State Harbor and Land Commission in a series of folios, which give plats of the lines, positions of triangulation stations, descriptions of boundary marks, extracts from laws by which the lines were fixed, and some historical matter.
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In order to make sense when reading this, you need as detailed a map as possible. However a road map will be useful. The more detailed the map the more you can see what is being described. On any map, however, if the Southwick Jog doesn't show, then you will be able to see little else.
Terms to know:
charter
grants (by who? to who?)
hereditaments
letters patents
court of chancery
Cape Mallabar (see Dexter)
Sagadahock
jurisdiction
bill in equity
court decree
commissioners (who do you think were these people?)
ex parte
plats
surveying terms:
English Miles; rods; chains and links
latitude and longitude
degrees ? minutes ´ seconds ˜
azimuth, bearing

NAD 1927
triangulation
miles (how many feet in a statue or land mile?)
Questions to think about as you read the Massachusetts boundary document.
--(general) Why was there so much 'problem' in settling early boundaries?
--what if a grant extended into another grant? why would this occur at all?
--what was contained in the 1691 charter? what was granted?
--why was the Mass-RI boundary specifically such a problem?
--why the Supreme Court involved?
--Is 41?55´ = 3 English miles south of the Charles River?
--When a mistake is made in a boundary, what is the legal principle the court follows in a subsequent dispute over it?
--what are the boundary monuments made of? why? how marked? wha happens if one gets 'lost'?
--how long did it take to finally agree on the Mass-RI line?
--what was the reason for the Southwick Jog? How big is it? check the maps.
--what part of the Connecticut River is used as a boundary between Massachusetts and Connecticut? What would you suppose would happen if the river changed course? Do you think this ever occurs? Can you cite an example where it would make a difference?
--how define a shoreline boundary when water levels fluctuate?
--what was the 'south sea' referred to west of New York?
--what was this business of the 'Boston Ten Towns'?
--can you see the 'Boston Corners' on the map?
--what natural feature was used to define the New Hampshire-Mass boundary? How was it used?
--how was the New Hampshire line confusing (that is, how interpreted differently by the two states)?
--what part of the Connecticut River was used as the Vermont boundary? what difference does this make?
(general)
Can you see any towns (names) in western Massachusetts taken from towns in the east? (see, for example, New Salem near Quabbin Reservoir, in the center west of the state). How many can you find? Look up the term toponomy.