1911: 'Abdu'l-Baha visited the Mayor of London

At the express wish of the Lord Mayor, ‘Abdu’l-Bahá paid him a visit early one morning at the Mansion House. The talk turned chiefly upon the social conditions of great cities, and ‘Abdu’l-Bahá said that London was the best regulated city he had seen.

He said: “Every man walking in the street is free as if he were in his own kingdom. There is a great spiritual light in London. The effort made for justice is real and in this country the law is the same for the poor as for the rich.” He took great interest in hearing of the care that is taken of prisoners as they leave jail, and spoke of the land being happy where the magistrates are as fathers to the people.

Before ‘Abdu’l-Bahá left London, he went to an East-end hospital to visit there a young writer lying seriously ill, who was very anxious to see him.

('Abdu'l-Baha in London)

How ‘Abdu’l-Baha signed His name in English: "abdul Baha abbas" – notice lowercase “a” and uppercase “B”

In contrast to many European languages, in Persian, personal pronouns are never capitalized. 'Abdu'l-Bahá followed this established rule and did not capitalize the pronouns that refer to Him. When the book was translated into English, the particular translator employed the convention, common in English, of capitalizing pronouns. It is interesting to note that when 'Abdu'l-Bahá signed His name in English, He used a combination of upper and lower case letters. He, typically, wrote "abdul Baha abbas" — the reference to Bahá'u'lláh being the only word He capitalized.

On the same principle it is the policy of the Universal House of Justice when approving translations of Tablets written by 'Abdu'l-Bahá, generally to have "me" and "my" and "mine" in lower case, following the example given by 'Abdu'l-Bahá in the writing of His own name in Roman letters. Pronouns used in referring to 'Abdu'l-Bahá by someone else, however, are normally capitalized. This policy can be seen in "Selections from the Writings of 'Abdu'l-Bahá" 

(From a Memorandum of the Research department of the Universal House of Justice dated 23 May 1991, attached to a letter dated 20 June, 1991, written on behalf of the Universal House of Justice to an individual believer)

An example of ‘Abdu’l-Baha’s humour and His ability to speak English

There is a note in ‘Abdu’l-Bahá’s character that has not been emphasized, and with which no idea of Him is complete. The impressive dignity which distinguishes His presence and bearing is occasionally lighted by a delicate and tactful humour, which is as unaffected as it is infectious and delightful.

On His last afternoon in London, a reporter called to ask Him of His future plans, finding Him surrounded by a number of friends who had called to bid Him good-bye. When, in answer to this query, ‘Abdu’l-Bahá told in perfect English of His intention to visit Paris and go from there to Alexandria, the press representative evinced surprise at His faultless pronunciation. Thereupon ‘Abdu’l-Bahá proceeded to march with a free stride up and down the flower-scented drawing room, His Oriental garb contrasting strangely with His modern surroundings; and, to the amusement of the assembly, uttered a string of elaborate English words, laughingly ending, “Very difficult English words I speak!” Then, a moment later, with the swift transition of one who knows both how to be grave and gay, He showed Himself terribly in earnest. 

(‘Abdu’l-Baha in London’)