"All Nature has a rhythm.  One need only listen."

            So said a nameless philosopher of yore, and the rangers of Arden have certainly taken that saying to heart.  Different than Thari and in many ways simpler, Cadence is the rhythmic language that the rangers of Arden have evolved to send and receive messages between themselves quickly, efficiently and sometimes silently.
            Cadence, being a patterned series of rhythms and spaces, is independent of its medium.  Thus, Cadence can be 'spoken' via the rapping of knife handle against a tree bole, the quick gestures of a hand to a patrol mate, and the bird-like whistle-calls across between patrols.  Or it can be heard in the pounding of hammer on tent peg, seen in the tugging of a branch against the wind and even occasionally, it is rumored, read from the wing-beats of a specially trained hawk.
            Cadence rhythms can also be represented as a series of slashes or dots and spaces or as an arrangement of stones and/or branches.  (Often the 'ranger markings' found in various places around Arden are exactly this, visual representations of the rhythms of Cadence.)  But as there is no standard for how to reproduce these rhythms, the markings can't truly be considered 'writing.'
           The rangers of Arden, however, are experts at recognizing Cadence no matter what form it takes.  And ingenious at producing Cadence in a myriad of different mediums.
           The rhythms of Cadence rarely correspond one-on-one directly to Thari words.  Instead, the rhythms 'translate' into concepts or phrases that the rangers of Arden find common and useful.
           'Spoken' Cadence is a series of brief succinct rhythms, meant to transmit information between the members of a patrol or between nearby coordinating patrols. These phrases tend to be very focused; "Danger, come quick." "3 men here." or "You go left."
           Representational Cadence, however, can be as succinct and as lacking in formal structure as 'spoken' Cadence.  Or it can be much more complex using rhythms that represent concepts / phrases rooted in ranger slang or patois.
           For example, one will not find a Cadence rhythm for 'His Majesty, King Oberon.'  Instead, the rhythm most commonly used to designate His Majesty is the descriptor rhythm (noticeable as such by its slower beats) for 'biggest' or 'largest', proceeded by a designator rhythm (typically sounded with short sharp beats) for 'Hide the hooch.'
           Typically, though, this elaborate a Cadence rhythm will only be found in representational form, or at use casually within a large encampment.  There is little need for this kind of communication while out on patrol.
            Longer Cadence messages do have a more formal 'grammar', though again, this is rarely used for the short messages needed between patrol mates and thus mostly only seen in representational Cadence or heard within the larger ranger encampments.  A lengthy Cadence message is usually broken into three parts separated by distinct pauses or 'rests' to use a musical term.
            The first section of such a message is lead by a rhythm that indicates the message's priority or urgency.  Following the priority/urgency rhythm is a series of beats that indicate the intended recipient and the sender of the message, typically -- though not always -- recipient rhythm first.  Every ranger, as well as every encampment, has their own signifying rhythm.  Thus, a message does not have to be designated to or from a certain person, but general camp to camp messages can be sent and received as well.
            (It should be noted that experienced or particularly sensitive rangers have been known to identify who is sending a message even without a personal signifier being used, recognizing Cadence speakers by their rhythmic 'accents' as it were.)
            These two or three rhythms -- the priority/urgency signifier, the recipient signifier and the sender signifier comprise the first third of a lengthy or representational Cadence message.  Then the rhythm pauses to indicate that the main body of the message is about to be transmitted.
            The main body of a Cadence message can be as varied or as long as needed, though most rangers strive for brevity.  After all, Cadence itself is a disturbance to the natural rhythms of Arden, something that many rangers are reluctant to make a regular practice of.
            The rhythms typically used in the main body of a lengthy Cadence message are also comprised of collapsed patois or slang phrases as opposed to 'words' spelled out in a code.  Thus, simple rhythms are used for phrases such as 'Typhooning here.', 'Bring your good arrows.', the mournful 'Last call.' or 'Skin's off and racked.'  (This latter being a phrase that the rangers use in a similar sense to 'It's all over but the shouting.')
            In addition to what could normally be considered the focus of the main body of a Cadence message, the rangers of Arden use a number of descriptor rhythms (again using slower beats.)  Numbers are counted out for small amounts.  Larger amounts have their own separate and unique rhythms.  Direction rhythms are adopted from the rangers' own unique spatial language.  Distances are designated by time and method, thus 'a 5 days walk' or 'a watch long ride' or even 'a night's flight.'
            This middle portion of a Cadence message is followed by yet another pause or rest.
            The last portion of a longer Cadence message is a simple sign-off, though there still are a number of different rhythms that can be used in this spot as well. 
            While technically the vast majority of rangers are illiterate or uneducated speakers of Thari, fluency in both 'spoken' and representational versions of Cadence is a requirement among the rangers of Arden.  And like many such requirements, one they are reluctant to share with outsiders.

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