Research Update

A couple of weeks ago, I wrote about an experiment I had completed, concerning an ancient Egyptian adhesive that was used in the most recent Sherlock Holmes. In the movie, a sandstone block had been broken into pieces, and glued together with a mixture of egg and honey, only to be washed away with the London rain.

With just the description in the movie, I set out several experiments to test Holmes’ deduction. I found that an egg and honey mixture did not glue together and showed obvious signs of tampering; also, although just a honey concoction glued the rock together, it left a very shiny residue. Both combinations dissolved with water. Also, the type of rocks I used were just ones I found and broke apart outside in the garden. I am no geologist, and nearly failed Geology 101 in college, so I have not clue what sandstone is, what it looks like, or where I would find it.

So, after writing up my experiment, I decided I would do a little more research into the details of this topic.

In the movie, Holmes called the solution an ancient Egyptian mild adhesive, containing a mixture of egg and honey (2009). Egg and honey, separately or together, were used during the ancient Egyptian times (Lucas, Nicholson). The Egyptians used both organic and non-organic materials for adhesives; organic adhesives included oils from animals, plant nectars, bitumen, beeswax, resin, honey, and egg (Lucas 2, Nicholson 475). Both the egg white and yolk can be used separately or together, as long as it has been diluted with water (Nicholson 476). Using just the yolk does cement objects together and will not dissolve after drying (Nicholson 476). Using only egg white will not join anything together. Before brushing any egg white onto anything, the white must be whipped to break up the protein albumen, which makes the white very stringy (Nicholson 475-476). Using the liquid underneath the froth, from after the whipping, it can be used as an organic adhesive (Nicholson 476).

According to Edward Keller, sandstone is a type of sedimentary rock (72). Sedimentary rocks that undergo chemical or physical changes as layers of sediment are pressed together (Keller 72). There are two types of sedimentary rocks; detrital, which are formed by parts of broken rock that form together, and chemical, created from deposits that come into contact with chemical or biochemical processes by particles dissolved in water (Keller 79). Sandstone is classified as a detrital sedimentary rock, and they type of stones is classified by grain size (Keller 81).

The strength of a particular rock is tested by the compressive strength measurement (compressing rocks to tests when breaks or fractures occur) (Keller B-1). Using the metric formula of N/m 2 (Newton per meter-squared), here is a table of rock strength, including sedimentary:

Table B-1: Compressive Strength Measurements
Rock	Type	Force (10tothe6 N/m2)
Igneous	Granite	100 to 280
Metamorphic	Quartzite	150 to 600
Sedimentary	Limestone	50 to 60
	Sandstone	40 to 100

The strength of the sandstone varies with the type (Keller B-1). For example, Graywacke is a mixture of sand that has several different grain sizes, making it very weak (Keller 81). Quartzose sandstone is made mostly of quartz and is one of the stronger types of sandstone (Keller 81). I am assuming the Blackwood’s tomb, if it were real, would have been made of a strong type of sandstone, possibly quartzose.

From the small amount of research I was able to accomplish without a college library or resources, I have been able to conclude two inquiries. Even without honey, the mixture of an egg can be used as an organic adhesive. Furthermore, sandstone can be used as part of a crypt as long as it is the stronger type. However, I have been unable to see whether or not sandstone, when broken, can holds its weight before a solution of egg and honey can be dissolved with water, or in the movie, rain. The only way to find this would be to recreate the movie. Seeing as I am unable to do that, or even find sandstone (or even the size of said sandstone), I can only rely on what I have found.

Using this information, in the coming days or weeks, I will recreate my experiment using new techniques to see if I can find a better conclusion.

Note: I am not a geologist, nor have I barely studied anything to make me an expert. Please take anything I write with a grain of salt! What I write up is how I understand it to be! Should I be wrong, please comment and I will change it!

If you have any ideas on how to continue this experiment, please comment! I have some ideas that will work but anything more is always helpful! Thanks!!!

Work Cited

Keller, Edward A. Introduction to Environmental Geology. 3^rd Edition. Pearson Education, Inc. New Jersey. 2005.

Lucas, Alfred and J.R. Harris. Ancient Egyptian Materials and Industries. Dover Publications, New York. 1999.

Nicholson, Paul T. and Ian Shaw. Ancient Egyptian Materials and Technology. Cambridge University Press. United Kingdom. 2000.

Richie, Guy (Director). 2009. Sherlock Holmes. Silver Pictures. Hollywood, CA