In the chest is the blessing of Mary Elisabeth who was born on May 18th 1852. The blessing took place on May 28th 1882 and was conducted by Elder A.M. Harmon who was the Pastoral Charge of the Newcastle-Upon-Tyne, Hull and Carlisle Conferences for the Church of the Latter Day Saints. He originally came from the Great Salt Valley (Information on Elder A.E. Harmon was found here: https://archive.org/stream/halfyearlyreport00newc/halfyearlyreport00newc_djvu.txt).
A transcription of the blessing is as follows (spellings as originally written):
Mary Elisabeth daughter of Robert and Hannah Telford, born May 18th 1852 in South Shields County of Durham and was blessed May 26th 1882 by Elder A.M. Harmon as follows.
In the name of Jesus of Nazareth I take you up in my arms, according to the pattern shown by our Lord and Saviour and by virtue of the Holy Priesthood bless you because thy parents desire it. I pray God my Heavenly Father through Jesus his Son to bless the(e) with health and strength and with a long life may she grow up in the fear and admonition of the Lord, and become a pattern of piety to those with whom able may associate.
Grant Heavenly Father to perserve her from all the snares of the wicked one from all the plagues of the last days, from pain disease and death and may she grow up in the Faith of Christ . be gathered to the Mountains of Ephraim and there be an ornament of Society, and be numbered with the Daughters of Zion. And as much as she is trained up in a right manner and in faithfulness by her parents she shall receive all those blessings upon thy head to be realised through the faith of thyself and parents. The destroying angel shall pass by thee and not have power to lay his Iron grasp until thy work is done upon the earth and thou shalt be perserved by the power of the Great God and your name is
Currently I do not know why this is in the chest, or if there is any relation to the Charlton/Caswell families. It is a bit of a mystery!