“We will use shallow-draft batteaux4 to transport our heavy equipment and supplies up the Kennebec, portage across the ‘Height of Land,’ to Lake Mégantic, and proceed downstream on the Chaudière to the St. Lawrence, directly across from Quebec.”

At this point, Captain Morgan said, “Sir, all this begs the question, when will we depart here? Winter is coming soon in these latitudes.”

Colonel Arnold nodded, paused, and said quietly, “I do not yet know our departure date. General Washington is waiting to hear from General Schuyler. All I have is this”—he handed Capt. Morgan a tiny piece of paper and an opened “Courier Ball.”5

“This was delivered to me late last night, by an Express Messenger from Albany. I opened the Courier Ball—thankfully he had not needed to swallow it—but I do not know this code.”

Captain Morgan looked at the tiny piece of paper:

THE EIGHTH MONTH OF THE YEAR OF OUR LORD, 1775

1T 3A 5T 3U 4A 5T 4U 3G 5T 2A 4S 5T

4A 1G 2U 4G 5A 2T 1S 3T 5T 1A 3U 3U 3T 3G 4U 1S 4A 5T

3U 2T 1A 3U 5T 1U 4G 4U 5T 2G 4A 5T 4U 3G 3G 5T

2G 2T 2T 5T 4U 3G 5T 4U 3T 1A 4U 1S 2T 5G

3A 3G 3U 4U 2A 3G 3A 1S 3T 5A 5T 4U 3G 5T

1G 3G 3A 3A 1A 3U 1U 5G

Then he said, “This is what we call a ‘calendar code.’ The key is the first line. The eighth month of the year is August. Our Committees of Safety have been using these codes for more than a year—too long in my estimation. Here’s how this one works.” With Col. Arnold looking over his shoulder, Capt. Morgan took a blank sheet of paper and explained:

“To create an ‘August code,’ write the letters of the month across the top line and beneath each letter of the month, place sequential letters of the alphabet like this, five rows and six columns. A number and a letter represent each letter of the coded message. So, the first letter of the message, 1T is F. The second letter, 3A is M. The third entry, 5T is a space. 3U is P, 4A is S, and so on . . .

“Now, see how quickly young Nathanael can decrypt this message.” I began to write . . .

FM PS TO GW [from Philip Schuyler to George Washington?]

SCHUYLER APPROVES

PLAN BUT IS TOO

ILL TO TRAVEL.

MONTGOMERY TO

COMMAND.

As I was decoding the message, Col. Arnold asked, “Captain, why do you say the Committees of Safety have been using this type of code too long?”