Monday, April 5, 1915
In rest billets northern outskirts of Estaires
The Battalion War Diarist wrote for this day: Nothing – No details recorded 
THIS DAY IN RMR HISTORY: “The militia department is forming a dental corps in connection with the overseas contingent and it is stated that Capt. J. A. Armstrong, the well-known dentist in this city, will have charge of the unit. While the order appointing Dr. Armstrong has not definitely gone through, it is understood that he will be the officer and that there will be dentists enlisted from all parts of Canada to make up the unit.
There has been so much difficulty about the teeth of the soldiers and so many men have had to have their teeth attended to by civilian dentists before and after they enlisted that it has been decided that there should be a unit to look after this work entirely. The details have not been very fully worked out, or at least have not been announced, but it is expected that the corps will accompany the overseas contingents to France.
Capt. J. A. Armstrong, in addition to his profession as a dentist, has been an enthusiastic soldier for a number of years and a strong supporter of rifle shooting. He was for some time commander of number 3 company of the 43rd regiment and is at present chairman of the executive of the 43rd rifle association. He is also a member of the public school board. It is understood that a number of the dentists of this city are ready to enlist as soon as the organization of the unit is definitely announced.” 
“The Canadian Army Dental Corps is believed by historians to be the first separate military dental service in the world. Individual dental officers had served previously as attachments to Canadian units in the lines of communication (the 1st Canadian Contingent had one dental surgeon unofficially attached to each Stationary and General Hospital). In early 1915, 19 officers and 38 other ranks were serving overseas in a dental capacity.
Once authorized in May 1915 by Militia Order 257, the CADC had an authorized strength overseas of 30 officers, 34 NCOs and 40 privates. By 11 November 1918 the CADC had 233 officers, 221 NCOs and 238 privates.” 
 War Diary, 14th Canadian Battalion, The Royal Montreal Regiment, April 5, 1915. Library and Archives Canada, Ottawa, http://data2.collectionscanada.ca/e/e044/e001089714.jpg
 Ottawa Evening Citizen, Ottawa, Ontario, Monday, April 5, 1915 pg. 1, col. 6.