What “early warning” system did the Rhode Island colonists have? How did they communicate danger throughout the state? They had no cellphones or internet, yet they still could issue warnings through a widespread system of beacons located on Rhode Island hills.
As early as 1667, when the British were at war with France and Holland, the General Assembly issued an order that a beacon signal be placed at Tonomy Hill on Aquidneck Island. It would signal with a fire at night or a smoke pot by day to warn of an invasion from the ocean. This beacon alerted all the other beacons across the colony.
Later, the Assembly ordered more beacons to be erected. They were probably at McSparren Hill in South Kingston, Mill Hill (Quaker) in Portsmouth and Prospect Hill in Providence. The Beacons were employed during the French and Indian Wars. In 1740 when England went to war with Spain, the Assembly ordered more beacons to be erected. They were placed at Block Island, Point Judith, Beaver Tail on Jamestown, and two more at Newport and Portsmouth. Butts Hill may have been a logical site for the second beacon in Portsmouth.
With the threat of war in 1775, the beacon system was re-established. In June of 1775 a post was established on Tower Hill in South Kingstown. Solomon Drowne, who taught at Brown, described the Providence pole to his brother in a letter dated August 12, 1775. “The Beacon Pole Mast is raised on the hill, ..nearly opposite the Church (likely First Baptist). I have heard said, is 80 feet higher than the top of the new meeting house steeple which is upward of 180 feet from the ground….”
A handbill was distributed that described the building of this tower. It was very simple in its design. There was a wooden shaft or mast, about 85 feet in height. It was braced at the foundation and had wooden pegs or steps, at regular intervals, coming from either side to enable a person to climb to the top. At the end of this shaft there was an iron crane. Hanging from the crane there was an iron basket that was filled with inflammable material. A house was built at the base to store the combustibles so they would be ready immediately.
Edward Field’s book on Rhode Island defenses quotes the handbill:
“……besides a strong battery and intrenchments on the river, there has been lately erected on the greatest eminence in this town, A BEACON for the purpose of alarming the country whenever it shall be-
come necessary in our defence, and as we doubt not of the readiness of our friends and brethren, both within and without this government, to give us every assistance in their power on such an occasion if timely apprized thereof. This is, therefore, to inform you that it is our urgent request that you all hold yourselves in readiness, and whenever you see said BEACON on fire you immediately and without delay, with the best accoutrements, warlike weapons, and stores you have by you, repair to the town of Providence, there to receive from the military officers present such orders as may be given by the authority of this jurisdiction for our common safety and defence. In case of an alarm we intend to fire the BEACON, and also discharge cannon to notify all to look out for the BEACON. Be it observed
and carefully remembered that the discharge of cannon Alone is not an alarm, but the firing of the BEACON itself, even without cannon, will be an alarm in all cases, excepting on Thursday, the 17th inst, at sunset, when the BEACON will be fired not as alarm, but that all may ascertain its bearings and fix such ranges as may secure them from a false alarm, and that they may know where to look for it hereafter. Whenever, you hear cannon look out for the BEACON.”
The Providence Beacon was tested on August 17, 1776. The light was seen in Newport, New London, Norwich and Pomfret, Connecticut.
In 1776 there was a pole erected on Beacon Pole Hill in Cumberland and on Chopmist Hill in Scituate. A fourth beacon was erected at Tomony Hill in Newport. This beacon was test fired on June 20th, 1776 and could be seen in Providence.
The beacons didn’t seem to provide a warning when the British invaded Aquidneck Island.

Resources:
Edward Field. Revolutionary Defences In Rhode Island, 1896.
“Beacon Pole Lights.” by Vincent H. Dexter. The Observer (Blackstone Valley), May 27, 1976.