fossil pollen is not an ordinary drilling operation involving 
repeated pouring of water or drilling mud into the hole, thus 
providing abundant opportunities for contamination. Core 
sampling in preparation for the construction of a skyscraper is 
an operation of considerable precision — one that is especially 
designed to yield undisturbed samples. Essentially it involves a 
series of tubes driven through the soil at successive levels. As 
the tubes are removed, they are immediately sealed at both 
ends with a special wax and are sent to the laboratory for 
various analyses. Engineers familiar with the problems of soil 
mechanics who have examined the data in Dr. Zeevaert’s 
article in Geotechnique (28) describe his operation as *‘ex- 
traordinarily careful and meticulous.” 
Dr. Zeevaert himself seems quite certain that the cores in 
which the fossil pollen was found are undisturbed samples. Ina 
letter of October 17, 1973, to Barghoorn, he wrote: 
Indeed the sampling of the material was performed with a special 
sampler to obtain undisturbed samples of the soil, useful to 
determine the natural compressibility and sheer strength prop- 
erties of the materials. Therefore, the samples taken were not 
disturbed or contaminated, they were ‘undisturbed samples’ 
used in soil mechanics to determine the ‘in situ’ mechanical 
properties of the materials. Therefore, you can be sure that the 
investigations made on these samples concerning the fossil 
maize pollen are reliable. 
We are inclined to accept Dr. Zeevaert’s statement as factual. 
We are pleased to note, in passing, that Dr. Zeevaert has 
recently been elected a foreign member of the United States 
National Academy of Engineering. 
Finally the fossil pollen itself demonstrates that it is not the 
product of modern contamination. It does so in this way: it Is 
one of the standard palynological techniques to prepare pollen 
for electron microscope studies by a treatment known as 
acetolysis (glacial acetic acid and concentrated sulfuric acid, 
9:1). This treatment is described in detail by Banerjee (29). 
Suffice it to say here that corn pollen when fresh resembles in 
shape an inflated basketball: when dry the shape of a deflated 
ball. Pollen from extant corn plants is restored to its original 
inflated shape when subjected to the acetolysis treatment 
(Plate I8A). But the pollen from the Bellas Artes does not 
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