it could not be we only had trains,no cars and no planes. Actually there are tribes who have still not heard the gospel and many in China and India though missionaries have been there there is still many people there that have not heard the gospel.
BTW if we went by that,I just read Mormon history here it is
In the years 1830 to 1899, it is estimated that about 12,827 missionaries were called to preach the gospel of Jesus Christ. From 1900 to 1950, the total number increased to 50,143. From 1951 through 1989, about 402,372 missionaries served. Since 1990, however, approximately 534,658 missionaries — or more than half of all missionaries who have ever served — have accepted the responsibility to share the message of the Church of Jesus Chris
So even if you were right you'd still be wrong. Mormon were in Missions by then.
The requirement is to taught in all NATIONS, and that in reality took place before 1844. Yes we had trains and many other means of travels.
From: http://barnabasyohannes.com/BibleBahai.htm
These are the three signs and their fulfillments.
1. The First: And this gospel of the kingdom will be preached in the whole world as a testimony to all nations, and then the end will come. (Matthew 24:14)
This prophecy was fulfilled in 1844 when the missionaries preached the Bible in the last nations of Central Africa and Tibet in China. Now, if you go to any nation in this world, you will find at least few Christians with the "gospel of the kingdom". The following two books confirm to this assertion:
'Christian missions began their activities amongst the African people in 1844.' (Year Book Guide to East Africa; Robert Hale Ltd).
'It was in 1842 that five treaty-ports in China were opened to commerce and to missions - advance steps in the opening of all China to the Gospel...' (Our Day in the Light of Prophecy; Spicer p.21).