CO885-(13-15) — Page 686

PUBLIC RECORD OFFICE

C.O.885

Reference :-

14 PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH—NOT TO

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diplomatic or other agents of the Governments of the South African Republic or Orange Free State be found within British jurisdiction.

2. From time to time Her Majesty's Government have been informed that such persons have penetrated into Her Majesty's dominions, not only in South Africa, but elsewhere, for the presumed purpose of assisting the enemy, and it is considered desirable that preparations should be made for dealing with any case of the kind which may arise.

3. I am accordingly to request you to take these matters into your consideration and to, report

1. Whether a diplomatic or other agent of the enemy Government, who is found (1) within British territory, or (2) on board a British, ship upon the high seas, or (3) within a British Protectorate, can be made a prisoner of war.

(a) If such person be a burgher of the South African Republic or Orange

Free State.

(b) If such person be the subject or citizen of a neutral Power.

·

2. If not, whether the arrest, or detention of such person can be justified on any

other, and, if so, on what grounds.

3. If detention or arrest is justifiable, by what persons should such detention or

arrest be effected.

4. If detention.or arrest be not justifiable, what course should be pursued with

regard to such persons.

5. Generally.

As this matter is somewhat of a pressing nature, I am to request the favour of an early reply.

Law Officers of the Crown.

1

I

am, &c.,

H. BERTRAM Cox.

26538/05

No. 242B.

(TRINIDAD: GENERAL.)

LAW OFFICERS to GENERAL POST OFFICE.

[Wireless Telegraphy: Validity of Marconi's Patents.] CASE SUBMITTED TO THE LAW OFFICERS.

December, 1899.

The opinion of the Law Officers is desired upon the validity of the patents known

as Marconi's patents, and now owned by the Wireless Telegraph Company, and on the relations to Mr. Marconi's system of an apparatus introduced to the notice of the Post Office by Herr Schaefer.

The report of the Consulting Engineer of the Department, Sir William Preece, upon the Marconi patents is forwarded for consideration.

The specifications of the several patents are also forwarded.

It appears to be an essential of Mr. Marconi's system that there should be used in the receiver an appliance called a coherer (in its first form the discovery of Mr. Edward Branly) which, in its normal state, is a non-conductor, but which becomes a conductor when actuated by an electric current, and that the receiver should also contain means by which the coherer is automatically again converted into a non- conductor or de-cohered. By this means a succession of currents and breaks is pro- duced, and signals are made by means of a local electrical circuit. Sir William Preece, it will be seen, considers that this salient feature of the system had been anticipated by Professor Oliver Lodge in 1889, and that Herr Popoff practically used apparatus of the same kind at Cronstadt in 1895. See on this subject Professor Lodge's lecture before the Royal Institution on "The Work of Hertz," delivered on the 1st of June. 1894, especially pages 16, 17 and 20, also letter of Herr Popoff in the "Electrician" of 10th December, 1897.

The feature of the Marconi system, by which communications are made at long distances, namely, the vertical wire, is not referred to in his original patents, although he does claim to use, in Claims 15 and 16 of the complete specification of his first patent (Application 2nd June, 1896) receivers and transmitters suspended upon poles. Sir William Preece suggests that, even with regard to this suspended apparatus, the patent is invalid, inasmuch as the complete specification is not founded upon anything appearing in the provisional specification.

Marconi's principal patent was applied for on the 2nd of June, 1996, and granted on the 2nd July, 1897. In December, 1897, he appears to have endeavoured to obtain

a patent for the use of the vertical wire, but without success, owing to the opposition of Professor Oliver Lodge and Dr. Alexander Muirhead.

In August, 1896, Captain Jackson was experimenting on board Her Majesty's ships with an apparatus containing a coherer of the same character as Marconi's and an automatic de-coherer (see his letter to Mr. Gavey of 31st October, 1897).

In September, 1897, the Engineers of the Post Office themselves conducted a careful series of experiments with vertical wires, without the assistance or presence of Mr. Marconi. This, it will be seen, was before the date at which he even applied for a patent specifically including the vertical wire (see Sir William Preece's official report of 28th October, 1897).

Herr Schaefer proposes to telegraph without wires by replacing the coherer used in Marconi's apparatus by a piece of ordinary looking-glass across the amalgam of which a fine cut has been made with a knife.

It appears that the looking-glass in this condition is a conductor, though a feeble one. When, however, an electric current is passed through the looking-glass, it becomes a non-conductor, but immediately afterwards resumes its condition of con- ductivity, Experiments have been made with Herr Schaefer's system by the Post Office: though not altogether satisfactory, they are thought to indicate lines by which, by gradual improvements of apparatus, success may eventually be gained.

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