Who were the Black Canons on the Augustinian Priory of Inchmahome in Scotland? Recently, while on holiday in Scotland, I visited the ruins of the Augustinian Priory of Inchmahome on the Lake of Mentieth, near to Aberfoyle and Loch Lomond.  The priory was founded in 1238 by the Earl of Menteith for a small community of Augustinian monks, including the Black Canons. The first Prior (Adam) arrived in 1296.  Source: Inchmahome Priory.

The Augustinian monks communicated by using sign language.  During meals, however, they were able to hear the word of God spoken.  St. Augustine apparently said: “Let not your mouths alone be exercised in receiving food; let your ears be also occupied in receiving the word of God”.

After rising at 02:30 for Nocturns, they would attend Matins at 06:00 where there would be readings and Prime.  Terce prayers and spoken Mass took place at 08:00 after which they would work.  At 12 noon there would be Sext prayers and sung Mass, followed by None prayers at 13:30. Dinner at 14:00 then they went back to work till 16:15. After that came Vespers prayers and Compline prayers.  They went to bed at 18:30.

Hard to imagine rising at 02:30 (especially in the winter) and then going to bed at 18:30, especially during a Scottish summer when the sun does not set till after 10 in the evening. However, I digress.  

As busy as the monks were all day, what was the purpose/function of the Black Canons?  Who were they and what did they do? Were the Black Canons founded by St. Columba in Scotland or did they originate with St. Augustine?  See: Canon regular (Wikipedia).

Any information on the Black Canons, their origins and function, would be appreciated. Also, if anyone could source the quote attested to St. Augustine that would be useful. Just curious!
"Black Canons" is another name for Augustinian canons regular. They are "black" because of their habit, according to the OED:


  black canon n. [from the colour of the habit worn; compare post-classical Latin canon niger (c 1220)] now chiefly hist. a canon regular of St Augustine (see note at canon n.2 1).


Canons regular are


  Priests who are bound by religious vows and who live in community under a distinctive rule. Originating in the eleventh century, in connection with the reform movement of Pope Gregory VII, they have mainly adopted the Rule of St. Augustine. 


A "canon" (Greek: κανών = "rule") is a priest who lives communally with other priests (although the exact meaning has changed throughout history), and "regular" means they follow a rule (Latin: regula) or conduct of life. The Church approves 4 main religious rules properly so-called:


St. Benedict's,
St. Basil's,
St. Augustine's (which the Dominicans also use), and
St. Francis of Assisi's.


Other religious orders use sign language, too, to foster an atmosphere of silence (cf. St. Benedict's Rule ch. 38: "should anything be wanted, let it be asked for rather by a sign than by a word.")

Rising in the middle of the night is normal for all orders' monks; the midnight prayers are called matins, which means "morning" (cf. St. Benedict's Rule ch. 8 or Ps. 118:62: "I rose at midnight to give praise to thee.").

What you quote of St. Augustine comes from ch. 3, ¶2 of his Rule. St. Benedict's Rule ch. 38 is similar; he prescribes a weekly reader, who reads aloud for the other monks while they eat: "[Spiritual] Reading must not be wanting at the table of the brethren when they are eating."