Although the General Manager of the Commonwealth Arsenal was appointed in 1916, it appears that the Arsenal began functioning as a record keeping body in January 1919. The first three Arsenal files were registered when files transferred from Department of Defence [I] were top-numbered on 25 January 1919.
 
Technical enquiries and discussions during 1915-1916 had led to the project for a central Commonwealth Arsenal to be established at Tuggeranong in the Federal Capital Territory being approved by the Commonwealth Government for appropriate action by the Department of Defence. In July 1916 Mr. A.E. Leighton, Manager of the Commonwealth Government Cordite Factory who was in London on loan to the British Ministry of Munitions, was offered the position of General Manager of the Commonwealth Arsenal. He accepted but continued working with the British. The British Ministry of Munitions recruited a number of Australians for service in England and these men, with some permanent officers of the Australian Department of Defence who went to England in early 1917, formed the nucleus of the Commonwealth Arsenal staff. While in England, officers specialised in different areas of munitions manufacture and related services. Two officers also visited
establishments in the United States.
 
Mr Leighton, the General Manager of the Commonwealth Arsenal, returned to Australia early in 1919 and was asked by the Government to report on the munitions supply problem in the light of experience gained from the 1914-1918 War.
 
During 1918 some doubt had arisen about placing a big industrial project at Tuggeranong and, in his report of 27 May 1919, Mr Leighton recommended the more feasible scheme of extending existing Defence factories and providing Scientific Laboratories, Inspector and proof facilities required for guiding commercial industries and for using the material resources of the country in time of war. (2) Coupled with public pressure to reduce Defence spending, this recommendation was accepted by the Government towards the end of 1919.
 
The role of the Commonwealth Arsenal then became one of expanding and developing the Government defence factories. The Arsenal had a Research Department which employed a number of chemists. Many of the chemists had worked in Great Britain during World War I and most returned to Australia in 1917 and 1918. They joined the staff of the Chemical Advisor to the Department of Defence and, in 1919, they came under the General Manager of the Arsenal. (3) At this time the position of Chemical Advisor became known as the Superintendent of
Laboratories. The Superintendent of Laboratories was the head of the Arsenal Laboratories and formed the nucleus of what became the Munitions Supply Branch Research Laboratories (CA 2554) which were opened in 1922.
 
The Commonwealth Arsenal appears to have had close links with the Chemical factories, that is, the Cordite Factory, Maribyrnong, Victoria and the Acetate of Lime Factory, Bulimba, Queensland. The Commonwealth Arsenal may have controlled these factories. (5)
 
In September 1920, a Board of Factory Administration [I] was appointed by the Government to administer and co-ordinate all the Government factories. The General Manager of the Arsenal was a Board member. The Board had power to purchase raw material, replace and repair existing plant, and order new equipment for the factories. (6) The Commonwealth Arsenal made recommendations on the appointment of senior staff, provision of new buildings and equipment and other policy matters relating to the factories to the Board of Factory Administration [I] .  

The relationship between the Board of Factory Administration [I] and the Commonwealth Arsenal is not precisely known. The Board may have been a superior agency to the Arsenal as requests for information and reports appear to have passed from the Central Administration of the Department of Defence to the Arsenal via the Board of Factory Administration [I]. Commonwealth Arsenal control records indicate that it was involved with many aspects of the day-to-day running of the various Government factories. However, what power if any the Arsenal had to direct the operation of the factories, either before or after the Board was formed, is not known.
 
The initial General Manager of the Commonwealth Arsenal was Mr A.E. Leighton. Major A.J. Gibson was the acting General Manager when Mr Leighton was absent. Mr Marcus Bell was the Superintendent of Laboratories. Prior to the formation of the Arsenal he was a Director of the Munitions Directorate and Chief Chemical Advisor to the Department of Defence.
 
The Commonwealth Arsenal changed its name on 24 August 1921 and became known as the Munitions Supply Branch.(7) The Branch was the
administrative arm of the Munitions Supply Board (CA 91) which took over control of the Government factories from the Board of Factory Administration [I] on 13 August 1921. The Chairman of the Munitions Supply Board was the Controller-General of Munitions Supply. This position was formerly known as the General Manager of the Arsenal.(8)  

No files of the Commonwealth Arsenal have been located. Those not destroyed may have been top-numbered into Munitions Supply Branch and Defence (Central Administration) files. The name and subject indexes and inwards correspondence registration booklets are held by Australian Archives, Victorian Branch.
 
References:
 
1. Commonwealth Arsenal, Inwards Correspondence Registration booklet,
   No. 85/1/- (Archives Accession MP 683, S11, B2)
 
2. A.E. Leighton, "Munitions Supply Laboratories, War History", P. 4
  (Archives Accession MP 891, S20, Box 1)
 
3. A.E Leighton,"Munitions Supply Laboratories, war History", p. 3
  (Archives Accession MP 891, S20, Box 1)
 
4. Department of Defence [III] Central Administration, file no.
   G.404/17/22 (Archives Accession MP 421, S.2, Box 1)
 
5. Department of Defence [II], Central Administration, file no.
   G.404/17/22 (Archives Accession MP 421, S2, Box 1); Commonwealth
   Government Factories: Reports for the year ended 30 June 1918
   in Commonwealth Parliamentary Papers, 1917-1919, Vol. IV, 
   pp. 1248-1250  
6. Commonwealth Statutory Rules, 1920, No. 152 Subject
7. Commonwealth Arsenal,  Index, "Organisation"
8. Commonwealth Arsenal, (Archives Accessing MP 441, S1, Box 2)
   Inwards correspondence registration Booklet, No. 85/1/-, entry 
   no. 50, (Archives Accession MP 683, S11, B2)
Historical agency address
Municipal Buildings, Cnr Queensberry & Errol Streets, North Melbourne

Subsequent agency unregistered

Munitions Supply Branch 
Subject to further research

Superior agency unregistered

Board of Factory Administration [I] 
Subject to further research