(Due to arrive Canberra 12.1.29)
My dear P.M.,
Your telegram with regard to the re-organisation of your own Department and of the External Affairs Department came as a surprise to me.  I shall be telegraphing you in the next few days after going into the matter with all concerned here.
I think there is little doubt that the Foreign Office would be able to find you a suitable man. The difficulty that occurs to me about borrowing an Englishman from the British Diplomatic Service is that he would have to be in charge of an executive Commonwealth department, which might be open to malignant criticism. It therefore occurred to me that either Colonel Rupert Ryan (son of the late Sir Charles Ryan of Melbourne), or, failing him, Allen Leeper , would be suitable.
Ryan is employed under the Foreign Office as Deputy Commissioner of the Rhineland Commission at Coblenz, but he is not a member of the Diplomatic Service. He was seconded from the Army at the end of the War to do this job and he has been there ever since and is universally spoken of as having done extremely well. He has the added advantage of being an Australian-but is saddled at the same time with the disadvantage of being my brother-in-law. 
Rupert Ryan is a particularly nice fellow, aged about 43, speaks French, German and Italian, has brains and character and a pleasant personality. He is well in touch with European affairs, but might be the better for a month or so in the Foreign Office before he went out to Australia, in order to bring himself up to date in respect of foreign affairs in other parts of the world.
Ryan married the daughter of the Earl of Erroll (who was Commissioner at Coblenz) and has a boy of 3 years old. His wife is rather a flighty young person, but would not necessarily come into the picture very much.
He has good administrative ability and gets on well with people.
Leeper is an Australian but, from our point of view, has the disadvantage of being a regular member of the British Diplomatic Service-although he could be seconded from that service to the Australian External Affairs Service.
I have discussed the question generally with Hankey , Amery , and Lindsay  and they all agree that as between the above two men Ryan is the more suitable from many points of view. I have no doubt personally that he would do the job extremely well.
Sir Austen Chamberlain  is at a League Council meeting in Switzerland, and Sir Ronald Lindsay is not able to give me a definite reply about the availability of either of these men (or of any other men that they might suggest) until he has heard Chamberlain's views. Ryan is in Coblenz where I have written him privately to find out his personal ideas on the subject-although without commitment, of course. I hope to have all the strings gathered together in a few days and will telegraph you.
As regards Officer , I should have thought that with the disturbance that Henderson's leaving will probably entail , Officer would have been valuable to you out there-at any rate for six months after Henderson leaves. I understand that you are about to get two new men into the External Affairs Department at Canberra, and I should have thought that Officer would have been wanted there to start them on the right path. However, if you can do without him there, he could either go into the Foreign Office for training or come into this office. As I am saying by telegram to you, it is my opinion (and Hankey's too) that he would get a much wider experience in this office than he would in the Foreign Office. I am going to suggest to you in my telegram that you might consider his coming into this office, from which he could usefully be attached to individual departments in the Foreign Office (such as the Far Eastern and American Departments) for a month at a time in order to study at close range the subjects that are particularly of interest to us, but not as a regular member of these departments. Also in order to complete his knowledge, I would suggest him spending some weeks at a time in the Dominions Office and also, possibly, in various branches of the War Office, Admiralty and Air Ministry, and the Special Branch at New Scotland Yard. He could usefully sandwich these temporary attachments in with doing actual work here with me. At the end of six or nine months of this sort of training, he would be, I think, fully competent either to take on this job of mine here or to take a useful place in the External Affairs Department at Canberra.
I have tried to show in the last few years that this small office here can keep you informed not only on Foreign Affairs but on Imperial Defence and a number of other related matters. My interpretation of the function of an External Affairs Department is a fairly wide one. In my opinion it should not concern itself narrowly with the aspect of affairs that concerns the Foreign Office, but should take into account defence and possibly, to a lesser extent, imperial economic matters. By myself here I have been able to do a certain amount in this fairly wide sphere and, if I had a man here to help me, we could cover this ground a good deal more fully.
Even if it is not appropriate for the External Affairs Department at Canberra to cope with this wide range of subjects in an executive way, there is no reason to my mind why they should not constitute themselves the collecting centre for such information which they could then see was distributed to the proper Commonwealth Departments.
In the past, it is my impression that this point of view has not been taken by Henderson and I expect that a good deal of the material that I have sent out in this regard has not found any useful home. However, the future may see this rectified.
I have not had any leave (other than two days) during this year and am rather feeling the need of a few weeks away from things. I am sorry it comes just when the subject of this letter has cropped up but I hope to be able to send you a fairly comprehensive telegram before I go.
I notice that in your telegram to me you specifically make no mention of the American appointment and I am asking you in my telegram if this means that you have decided to deal with this position in some other way.  I may say that, if you want me to do so, I am quite willing to stay on here in London for the next three years, or to start the new appointment in Washington. If I can be of service to you, I am entirely willing.
If you send Officer here for six or nine months under me, I am sure he would be able to do this job at the end of that time, and if you then want to send me to Washington, Officer could take over this work here.
I am, Yours sincerely, R.G. CASEY