Feature Story

Ground Thawer for Winter Grave Digging

VOCA Editor's Note: In the April 1920 issue of Park and Cemetery, a monthly magazine devoted to all things public park and cemetery, we find this labor saving story.

Rose Hill Cemetery, Chicago has developed under the exigencies of the recent severe and continuous winter, a type of simple and practical ground thawing furnace that has been the means of effecting a saving of about fifty per cent in the cost of winter grave digging and in lessening the hardships of winter interment work to such an extent as to make it not only economical but a valuable aid in conserving the strength and efficiency of the men.

The device consists of a simple sheet iron box 48 inches long and about 18 inches high, open at both bottom and top, the sides sloping inward so that the top opening is about half of the width at the bottom. While the four-foot length does not of course cover the entire length of the grave, it has proven perfectly efficient in thawing out the ground. The Rose Hill force, however, recommends that the boxes be made as long as five feet.


The box is placed over the grave and filled with coal. The fire is lighted in the afternoon, and left to burn all night. In the morning the coal is all consumed and the grave ready to dig, with the ground thoroughly thawed out down to the frost line. The cheapest grade of Illinois coal is used, as this has been more satisfactory than either coke or hard coal. The cost for coal and in distributing and starting the fire about $1.00. Two men are used and it takes about one half the time required for digging without thawing. Superintendent Wallis says of the results obtained: “This saving together with the saving of man power, which is so essential and should be appreciated by the men, has proved very satisfactory to us the past winter when we had four and one half feet of frost. This probably is not so economical as dynamite, but I do feel it is safer, especially should it be necessary to use inexperienced men”. (VOCA Editor’s Note: YA THINK?).

When the Rose Hill force first began the use of the ground heater they had one made up, and used it without a cover, relying on the taper of the sides to produce enough draft. With further experiments, however, they find that it gives better results to have about 36 inches of the top covered, leaving an opening about a foot square at the end, thus forming a kind of chimney and securing more draft. The opening should be at the end away from the direction from which the wind is coming. The sides are flanged at the end and bolted to the end piece, and a handle is bolted on either end. The construction is very simple, and any sheet iron worker could make the device. The Rose Hill furnaces are made by John Mohr & Sons, 349 W Illinois St, Chicago and cost about twelve dollars each. The device has been such a pronounced success that four more furnaces have been ordered after the results with the first one had been noted.


The men are all enthusiastic about the results and appreciate very much the help of “Lizzie” as they affectionately term the new grave digger's winter assistant.