Engineering Features of a Modern Cemetery
Beginning as early as 1825 Dr. Jacob Bigelow started the movement for the removal of human bodies from church cellars and other sepulture in the city of Boston to the better method of laying out a garden cemetery which should be located a few miles from the cities with the primary object in view of protecting the general health of the public and as stated in his own words "To desire the institution of a suburban cemetery in which the beauties of nature should as far as possible relieve from their repulsive features the tenements of the deceased; and in which at the same time some consolation to survivors might be sought in gratifying, as far as possible, the last social and kindred instincts of our nature.” It was indeed a far sighted idea on the part of Dr. Bigelow and one which spread rapidly in succeeding years to all parts of the United States. The Modern Cemetery with its engineering and landscape features of today is a logical outcome of this initial movement.
It is now over one hundred years since this important step for a better disposition of human remains started and in this period of time there have been many changes and additions to the original conception of what a cemetery should be so that the larger cemeteries of the present time represent the collective human experience of many minds and probably the largest single influence in this period has been the American Association of Cemetery Superintendents. In such a gathering as this, which is the fortieth that has assembled, it is inevitable that ideas and ideals start for or realized by its present members, and it is with this thought in mind that I am going to review particularly the engineering characteristics which we may find in a cemetery and which are naturally the outcome of many years of experience in this special line of work.
LANDSCAPE: I have divided the particular engineering features under the headings with the sub-division illustrating the details as applied to this work. The outstanding feature of course is landscape work. This necessitates a study of topography of the land, a study of roads and paths, trees, shrubs and equipment which will reveal to the best advantage the natural landscape which may be available. Constructions have been made so that vistas thru the trees and shrubs will show ponds and lakes, monuments and slightly beds and observation towers which are existent. Embankments and special ground are planted to shrubs, vines and trees not only for effective landscape but also to lessen the maintenance of certain grounds.
PLANT AND MAINTENANCE: In order to carry out the construction work and maintenance of a cemetery it is of course essential to have a plant with proper buildings thereon which shall necessitate the least amount of steps and in the larger cemetery adjacent to these buildings a railroad side track is very convenient, not only for unloading cement, sand and necessary material but also for the purpose of taking in monuments and mausoleum granite. In addition to side track facilities we have the following buildings: Garage for trucks, Blacksmith Shop, Carpenter Shop, Mechanics Shed for tools and derricks, Laborers Shed and tools, Grass-cutters Shed, Perpetual Care Shed, Housing for Power Sprayer, Steam Roller, Gas Engine and pump, Men’s Lounging room and Yard Office. One engineer says "Our structures begin to wear out even before they are completed, hence the necessity for maintenance." Depreciation and the need of repairs for buildings and equipment are self evident to anyone and the condition of the plant is dependent upon constant inspection followed by decision and action to hold every part of it to as near as possible 100 percent maintenance. When our perpetual care fund runs up to a considerable amount it seems that the word maintenance covers the greater part of our work.
ROADS: Due to the demand of present traffic conditions it essential that every cemetery shall have good roads and it therefore becomes part of the work of modern cemeteries to build their own roads and in this work there is a very large opportunity for every cemetery superintendent to improve the existing grades as well as to build roads of such material and in such a manner that the grades are easy that the surface material will stay for a great many years and that no weeds will have an opportunity to grow. Preliminary work in road construction necessitates proper drainage by piping and this in turn would become also the problem of proper surface drainage in every part of the grounds so that the soil in every section is clear and drained of water in winter as well as in summer. In order to carry this thru it is sometimes necessary to recognize the mistakes made in early days and consequently raise the grades of paths that the roadways shall always be the lowest point in the topography of the grounds with the exception of course of any natural lakes or ponds that exist.
Our experience so far leads us to construct the roads as follows: The standard road is 18' in width. After the road is brought to proper grade by excavation and fill and the gravel for proper material for the road bed spread the width of the roadway, the whole bed is thoroughly rolled being drenched with water at the same time so that a solid and substantial road bed will be ready to receive the constructed surface. The construction surface begins with 4" to 5" of 2½" crushed stone thoroughly rolled and it is a fact that at the present time particularly where the road slopes in the direction of its length that the surface is made practically flat but where the road is almost level a crown should not exceed 2" in an 18' width. The six to twelve inch crown on a gravel road of years gone by is really dangerous construction for present traffic. After the 2½ crushed stone has been thoroughly rolled all depressions noted, and properly filled, then the whole is covered with tarvia or other bitulithic material at the rate of 1½-2 gallons per square yard. After this tarvia is spread, ½" crushed stone in as thin a layer as possible is spread over this surface. This is then thoroughly rolled again and after being thoroughly rolled is covered with one coat of tarvia at about ½ gallon to the yard which we call the sealing coat. Next a very thin layer of clean sharp sand is scattered over this surface and worn in by traffic.
I have known a road constructed in this manner to lay for almost twenty years without any further treatment than occasional coating of tarvia and sand. I believe a road of this nature is one of the least expensive that any cemetery can build. Concrete for road construction in my judgment in a cemetery is unnecessary, except in special cases where grades are so steep that a roller will not work efficiently. We have such a problem and are building this small piece of road according to the Mass. State Highway Specification.
About twelve years ago after completing a road, I remember the roller engineer telling me that we had so improved the grade on this particular piece of road that he only required one half the steam pressure to go over the hill that he had to have before; what this means in the saving of foot power and horse power I will leave to your imagination but I'll wager that the foot power or horse power saved will never be known to the ones who are using this highway. However, this thought should never prevent us from doing all our construction work as the best engineering science demands it should be done.
WATER SUPPLY: Due to the large amount of vegetation which is an essential part of a good cemetery, a water supply is very necessary equipment and a great many cemeteries for this reason have their own pumping stations. At Mount Auburn Cemetery this equipment includes 28-2½" driven wells varying in depth from 52' to 125'. It is a fact that practically all water from driven wells contains a large amount of iron and iron in water for cemetery purposes is very undesirable for the reason that it discolors all stonework with which it comes in contact.
By means of aerating equipment the iron in the water is readily oxidized, the water then flows over charcoal beds and sand filters which not only entirely remove the iron but also other impurities that may be in the water. From the sand filters the water flows into a clear water basin and is then pumped up to the reservoir where it flows into the mains to all parts of the grounds. There are also fountains and ornamental sprays which if used in connection with the water supply of a city would probably be considered 'an unnecessary luxury. The Pumping Station contains a low lift pump driven by a 5 Horse Power Electric Motor which pumps the water from the wells to the aerator and onto the charcoal and filter beds and also a high lift pump driven by a 25 horse power motor which pumps the water from the clear water basin up to the reservoir. Both pumps are automatic in control being governed by floats actuating electric switches.
CONCRETE: At the present time concrete more than any other material is being used in modern constructions and engineering work. In our case concrete is used as follows: Foundations for monuments and mausoleums, for paths, roads, chimneys, benches and greenhouse constructions. Our Half Hardy House is practically all concrete and we have a concrete wall 10' high around one half mile of the cemetery which at the present time due to its adaptability not only protects that part of the grounds particularly well but because of its lending itself so well for planting purposes is more ornamental than any form of cemetery fence which I have seen. The only wall that possibly equals a concrete wall for protection and ornamentation would be of brick construction such as one sees in English gardens but this would be more expensive and not as durable.
CREMATORY: I am in accord with the late James Currie of Milwaukee, that the day is not far distant, in fact, may be said to be already here when no cemetery of any importance will be fully prepared to accommodate its patrons if not equipped with a crematory as a medium for the disposal of the dead.
The cemetery and crematory should not be considered as standing in opposite and antagonistic positions and that cremation is not inimicable but in reality conducive to the prosperity of a cemetery."
The crematory at Mount Auburn Cemetery consists of a well designed chapel, the upper part of which contains an organ, vestry and all the necessary background for holding: proper services. In the basement of this building are tour retorts capable of taking care of twenty-five to thirty bodies in one day. In back of the retorts towards the rear of the building is a subterranean passage about 40' in length and leading northerly away from the main building, this enters into a building which is made entirely of concrete and which is wholly underground except the glass skylight overhead which measures 12' x 10'. In this engine room is a centrifugal compressor which is capable of delivering 1600 feet of free air a minute to the retorts above. This is operated by a 25 Horse Power electric motor being supplied with current from the local Electric Light Company. As an auxiliary on the opposite side of the engine room is a gas engine coupled to a Root's blower which can be used if the electricity should for some reason not be available. Just outside of the engine room but adjacent to it is a heating plant for all buildings of the crematory unit. This uses oil as fuel, is automatically operated and as a matter of fact is the best heating unit we have in connection with the whole cemetery.
The efficient operation of a crematory is maintained by a knowledge of chemistry as regards combustion and fuel oil; the design and operation necessitates engineering skill which shall assure the elimination of objectionable features, maintain quietness and speed in operation and the creation in the immediate vicinity of an atmosphere which will reflect peace and quietness which is so essential for the people who at this time require the use of this equipment.
MECHANICAL: The necessity for mechanical knowledge in the maintenance of plant equipment is illustrated every day in the ordinary operation of a cemetery and I think is evident in the things which I have enumerated.
CHEMISTRY: In the healthy upkeep of the vegetation which covers so much area, a knowledge of as much chemistry as will lead to successful spraying and fumigation to hold in check or to eliminate entirely insect pests and diseases which are apparently always evident, is certainly a desirable asset for the cemetery manager or his assistants to have.
I am inclined to believe that the average man does not realize that the conducting of a cemetery is a technical business requiring training, skill and experience and the primary purpose of this paper is to show in part some of the technical features involved in the establishing and maintaining of a cemetery as required under present conditions.
From the publication:
AACS - Proceedings of the 40th Annual Convention
October 11, 12 and 13, 1926