About 7 years ago I saw a small article on micro-film in the Columbus newspaper at the main Columbus, Ohio library in which it stated that the rostrum was built in 1918 and was built by the US Corps of engineers. What I just said should be taken only as hearsay because when I went back to the library to find the exact date of the paper I could not find the article again. Could my memory be going gone bad? It would appear so since I can't find the article again. The Hill-top Society have some of the best researchers when it comes to Camp Chase. If I understand some of them correctly they believe the rostrum was built in the 1930's. Until I can find that article again, I must yield to their knowledge.
Also notice on the map David that includes the rostrum that the graves are opposite. For example grave 1 in row 1 is now where grave 23 in row 1 is and vice-versa. In my opinion the 1867 map is incorrect. Looking at the very first grave that of John R. Horton buried August 4, 1863 you would not bury the first man under or nearly under the fence. Rather you would give yourself plenty of room. Of course there were no fences I know of during the War. However the property line was very close to where grave #23 is today. The first fences were put around the cemetery from some of the planks of the Camp Chase dwellings just after the War.
And now for your recent questions:
You are correct in that the Blue Ridge Marble Company did make the stones from the 1907 Register that you have seen. However, you will notice that civilians are not listed on the 1907 only military. Yet we see civilian stones at the Camp Chase Cemetery. The 1912 Register does have the civilians and military for the Chase stones. I do not remember exactly when the US government allowed Confederate civilians to have stones but the date of 1906 does comes to mind. If that is the case then the Blue Ridge Marble Company could have included the stones for the civilians but they were not listed on the 1907 Register because that was a government printing and only the military men were mentioned.
Col. Knauss is going to get his information from Chaplain D.W. Tolford. We have to remember that William H. Knauss did not move to Columbus, Ohio until the late 1880's, or early 1890's. And when he did so he was involved in real estate. Chaplain Tolford was in the military with the 10th Iowa Infantry and was in the battle of Shiloh as an example. He had some ties to Ohio and shortly after the War was in charge of all reinterrments for Civil War soldiers in the state of Ohio and the marking of all Civil War graves.
His job was to put all of the Confederate dead to two places in the State, Camp Chase and Johnson's Island. He also reinterred many Union soldiers also.
Chaplain Tolford did the best job under the conditions that he had in my opinion and remains one of Camp Chase's unsung heroes. He went from grave to grave across the State of Ohio and wrote down the decaying information from the wooden headboards including Camp Chase. Needless to say he made mistakes. Imagine writing down thousands of names in 1866-67 on pieces of paper not including the weather conditions and water that might make the names run and the winter months etc. In addition to that he had to write down what he hoped that others had done correctly. If someone at the time wrote down bad information on the wooden headboard then how would he know the difference? A good example of this would be Jacob Lake. Lake was buried in the Southeast Cemetery in Columbus, Ohio along with Union Soldiers and Confederate soldiers. His wooden headboard probably read something like this: Jacob Lake Company G 90th Penn. One of two things happened. Either the information was incorrect or more likely the 3, 4 and 5 o'clock postion of the P started to decay and it looked like a T. However, it happened Jacob Lake would be known as a Confederate even though he was a Union soldier. His body was removed from the Southeast Cemetery in May of 1869 and has been in the Camp Chase Confederate Cemetery ever since. It was not Captain Irving's fault who was in charge of removing the bodies but that of Chaplain Tolford's if blame has to be made. Tolford left behind at least 8 Confederates at Camp Dennison. Why? don't know but a mistake was made, they should have been brought up with the other 31 to Chase. In July of 1869 those Confederates left behind were taken to the Spring Grove Cemetery near Cincinnati. We should be indebted to Tolford as his work was amazing and he found hundreds of mistakes that were made.
The stones for Camp Chase were brought to Columbus, Ohio via rail from Nelson, Georgia. I don't recall having heard of anyone from Nelson, Georgia setting the stones at Chase. They would have been brought from the railroad depot in Columbus, a distance of about 4 miles with horses and wagons I would assume.
A private firm buried both the Union and Confederate soldiers at the Southeast Cemetery unitl the Camp Chase Cemetery was started on August 1, 1863. I don't know if they continued to bury the Confederate dead at the Chase Cemetery after its establishment. I have not quite researched that area as of yet.