aly REPORT 
possible strength as a cement producing state. A series of publications 
was therefore projected, of which this 1s one, to take up the whole sub- 
ject de novo, and bring the matter to public attention in the light of mod- 
-ern industrial conditions. 
The cement industry, as is well shown in Bulletin Three, is one 
of the most wonderful examples of the splendid virility of the American 
nation. In twenty years we have taken it up, perfected it, improved its 
manufacture, found new uses for it, and ‘after supplying our own fabu- 
lously increasing needs, are beginning to look covetously upon the markets 
of the world, long occupied by the English and Germans. ‘This story 
reads like a romance, and we little appreciate even now how wonderful an 
expansion yet lies ahead of us in the use of this supremely convenient and 
serviceable material. 
The Geological Survey of Ohio has examined the cement industry 
before; a very valuable article on that subject appeared in Vol. VI, pub- 
lished in 1888, from the pen of Prof. N. W. Lord. But since that time the 
conditions have altered so fundamentally, that it was thought best to take 
the subject up and thoroughly discuss its present status. 
Bulletin No. 2 1s by Prof. Frank Harvey Eno, Associate Professor 
of Civil Engineering in the Ohio State University. Professor Eno has 
had much experience in the use of cements; he has laboriously searched 
the literature of the subject; he has traveled widely to visit and study the 
typical and important examples of all the uses to which cement is being 
put. He has, in accordance with my instructions, made this work a pop- 
ular one — avoiding the symbols of the chemist or the mathematics of the 
engineer. He has written to reach the people —the great body on whose 
increasing intelligence in the use of cements depends the still greater 
expansion of the industry of the future. 
While this bulletin is not the record of new and exhaustive researches 
in this field, at least to any important degree, and was not intended even 
to contain a detailed discussion of the many mooted points in the theory 
of cements, it must not be supposed that it is either loose in its state- 
‘ments or so general as to be of no value. It has been the aim to present 
the facts, with such few theoretical considerations as are now generally 
accepted, in such a simple and clear manner that it will be understood 
‘by all. | . 
FOURTH. THE MANUFACTURE OF HYDRAULIC CEMENTS. 
The task of studying and reporting upon the manufacture of 
hydraulic cements was given to Mr. Albert V. Bleininger, at that time 
an assistant in the Department of Ceramics of the Ohio State University. 
The marvelous expansion in recent years in hydraulic cement manu- 
facture and the Portland cement industry, in particular, has resulted in a 
‘condition which is undesirable in several respects. Accurate information 
-as to the nature of the raw materials best suited has not been available 
