I have heard from the Charles Blockson Collection at Temple University. Although I had been led to believe that the Collection held positive primary documentation for the Lawn Jockey/Jocko statue as an UGRR signal, they apparently do not. This is their response to my query.

"Dear Dr. Kate Clifford Larson:

At the Blockson Collection we don't have a primary document supporting the claim with regards to the use of the Lantern Holder as an UGRR signal. Below is an excerpt from Mr.
Charles L. Blockson's book entilted Pennsylvania's Black History (Philadelphia, Pennsylvania: Portfolio Associates, 1975), 140:

"The Lantern Holder-Black historian Earl Kroger recently revealed that, historically, the lantern holder figurine symbolized a twelve year old black boy named Jocko who held a group of horses near Trenton, New Jersey, as George Washington's army crossed the Delaware River on December 24, 1776. Jocko was frozen to death performing this service. Impressed by this young man, George Washington had a statue erected on his lawn at Mount Vernon honoring Jocko. Replicas of the Jocko statue have changed over the years.
Prior to the CIvil War, it was the costom of some Abolitionists to place small figurines holding lanterns on their property to alert fugitives that their home was a station on the Underground Railroad."

Below is another excerpt from a document ("curriculum package") entitled, Beyond Adversity: African-Americans' Struggle for Equality in Western pennsylvania, 1750-1990 (Pittsburgh, Pennsylvania: Museum Programs Division, Historical Society of Western Pennsylvania, 1993), p. 12:

"Over the years, there has been some controversy concerning the presence of small African-American statues depicting a jockey that appears on the lawns of many houses. The legend
of this statue tells a story of hope for many fugitive slaves traveling on the Underground Railroad: It was a custom of some station masters on he Underground Railroad to place a small statue of a Black boy holding a lantern on their properties to alert runaways that their homes were
stations. Sometimes this small figurine or statue served as a hitching post to which horses could be tied. These were often placed in the front of the house or near a barn where runaways could locate them. Agents told passengers that the owners would aid them ... The people who worked on the Underground Railroad told the story to the slaves, encouraging them to remain brave."

I hope this helps,

Aslaku Berhanu"

So, this was my response to their prompt reply and help in clearing this issue up:

"Dear Aslaku Berhanu,

Thank you so much for your detailed response. It seems then that there is a short trail of late 20th century reference to this phenomenon of the lawn jockey myth. Earl Koger was the first person to publicize this story of "Jocko" the faithful black boy who froze to death holding George Washington's horse as Washington crossed the Delaware in 1776, and the statue that was derived from the boy's death. No where in 200 years of history had the story ever been recorded. Mt. Vernon's extensive records show no statue to a black boy, nor in Washington's extensive records, letters, journals, etc., nor of any of his staff (military or otherwise.) There is no record of a Thomas Graves in the Continental Army (and there are detailed records of black volunteers and fugitives who joined). The lawn jockey statue was never called "Jocko" until after the 1970s when Koger finally published his story. The statues, which began manufacture around late 1864 and 1865, were orginally hitching posts in the form of an enslaved boy, in tattered clothes, sitting atop a bale of cotton with his hand outstretched with a ring to hitch a horse. They were sold primarily in the New Orleans market (then occupied by the Union). The statue evolved over the next few years, so that by the 1870s, it had taken the form of a black groomsman The statue was known variously as the "Sambo Hitching Post", "Negro Boy Hitching Post", and "Nigger Hitching Post". "Lawn Jockey" doesn't appear until the 20th century.

But the "Jocko" story, I believe, is a separate phenomenon from the purported use of the groomsman statue as an UGRR signal. Since your collection does not have the primary documentation that I was led to believe you have, then I must conclude that the story originated with Wilbur Siebert in his 1951 volume "Mysteries of the Ohio's Underground Railroad," in which he claims that the Piatt's of West Liberty, Ohio, ran an UGRR station. Oddly, though he identifies the Piatt family of West Liberty, Ohio, as pro-slavery in his research files used for his 1898 original Underground Railroad book, it appears that he ignores that research and claims, over fifty years later, that the Piatt's were UGRR agents, who used a lawn jockey statue as their safe house signal. His own research says this is not true, and the lawn jockey he describes and shows in his book could not have been manufactured until well after the Civil War, and possibly the 20th century. I cannot account for Siebert ignoring his own 1st person eye-witness testimony from the 1890s - which, by the way, identifies and credits numerous black UGRR operators in that region.

The Pennsylvania curriculum guide seems to merely repeat Koger's unsubtantiated work and Mr. Blockson's work, which relies on Koger's work.

I will send along a copy of my article once it is completed, for your files. I know that many people may be disappointed with this re-examination of the Jocko lawn jockey UGRR signal story, but it important not to perpetuate myths. The great tragedy is that the original hitching post statue was an incredibly racist representation of the enslavement of young children, evolving into the black groomsman who replaced real enslaved men who were now free, but whose service and embodiment of white wealth and power could now only be had in a statue - and could now be owned by thousands of middle class Americans who could no longer have a slave of their very own.

Thanks again for your help.

Best regards,
Kate"

I will let everyone know what sort of response I get from the Piatt House museum.

Kate