It is not necessary to go to the posted coordinates to obtain the log. The posted coordinates are along Burnett St, which was the location of the British headquarters during the occupation of New Brunswick. The actual building is long gone.
On December 1, 1776, British forces led by William Howe landed on the banks of the Raritan opposite New Brunswick. With a force double that of Washington's, the Colonial Army retreated in the face of superior numbers. That began an occupation of New Bruswick that would last until June 22, 1777.

Howe and Cornwallis Entering New Brunswick. Mural on display at the New Brunswick Post Office
During their stay, the British Headquarters was at the home of Colonel John Neilson. Neilson was a strong supporter of independence. The home was on Burnett Street, which ran along the route now occupied by Route 18. Everything in this section of New Brunswick has been torn down.

Neilson's home on Burnett St, date unknown. It was the Headquarters of the British Occupation of New Brunswick
Howe initially offered--and 2,500 accepted--protection to anyone signing an oath to the crown. But as the number of British troops in New Brunswick swelled to more than 6,000, they had to be fed. As they foraged, they were subjected to constant harassment from colonial raids. And a bridge needed to be built across the Raritan, which required lumber. And the large Hessian military presence consisted of troops who couldn't speak English, so orders of protection were not always understood. All of this resulted in a level of hostilities to surrounding residents that caused many to flee the area. One historian has suggested that as the occupation went on, there were far more British troops in the area than residents.
In June of 1778, Henry Clinton--then leading the British--was ordered to send 5,000 troops to the Caribbean and abandon Philadelphia in favor of New York with the news that the French had entered the war. The French entrance into the war completely altered the landscape in New Jersey--the Caribbean was much more valuable to the British than the northern colonies, and with the possibility of a French fleet attacking valuable British possessions, it could no longer be left undefended. Furthermore, the French fleet was threatening New England, and the British did not have the luxury of occupying New Jersey and defending New York and Boston from a large French force.
To obtain the coordinates to the cache, answer the following question: How many days did British troops occupy New Brunswick from December 1776 to June 1777?

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