From The National Cyclopedia of American Biography, Vol. 60, 1981         
(paragraph breaks inserted)

CROM, John Maurice, engineer and inventor, was born in Morrison, Ill., Mar. 9,
1886, son of James Ambrose and Clara Lydia (Kennedy) Crom, grandson of Martin V.
and Rebecca (Overholser) Crom, and great-grandson of Jacob and Anna (Overholser)
Crom.  His father was a farmer.  

John M. Crom completed high school in Twin Falls, Idaho, attended the State 
Normal School, Lewjston, Idaho, and was graduated B.S. in civil engineering 
in 1911 at the University of Idaho.  In 1912 he became city engineer for 
Cashmere, Wash., and remained there until 1915 when he took a post as 
an engineer with the firm of Alexander Potter, Engineers, New York City.

After four years with that firm, he joined the Cement Gun Co., Allentown, Pa., 
as salesman-engineer and district manager of its office in Chicago, Ill.  
The business introduced into many new fields Gunite, a mixture of cement, sand, 
and water that was applied by pneumatic pressure through a specially adapted 
hose and was suited particularly for use as underground support in mines and 
for refractory application in steel mills.  

He left that company in 1927 and organized the Gunite contracting firm of Crom 
& Lindberg in Texas; that company applied millions of square feet of gunite or 
shotcrete for irrigation canal purposes in the lower Rio Grande Valley of Texas.
In 1933 he organized and was half owner of The Preload Company of New York,
New York City, which became the foremost prestressing company.  In 1947 it built
and erected the first prestressed concrete bridge in this country, the Walnut 
Lane Bridge, Philadelphia, Pa.  

Crom invented wire-wound circular prestressing (U.S. Pat. No. 2,372,060) in 1942
and composite diaphragm steel-shotcrete prestressed cylindrical water storage 
reservoirs (Pat. No. 2,370,780) in 1944, and the company, through contracting 
and licensing, built thousands of prestressed tanks throughout the world.
Early attempts at prestressing for tanks was unreliable because in time shrinkage
and plastic flow in the concrete were unpredictable.  It was not until the
1930s when Crom, in collaboration with leading technical institutions in this 
country and Canada, developed methods whereby shrinkage and plastic flow in
concrete and creep in steel could be predicted and compensation made in the 
design of circular structures.  Crom then devoted his energies to finding 
prestressing materials with proper stress capacity and found that high-strength
steel wire was the answer.  So that circular prestressed tanks could be universally
accepted, he devised the composite wall system, which consisted of a corrugated
steel shell cylinder to eliminate through-wall leakage, and shotcrete encasement
on both sides of the steel liner to make the wall the desired thickness.  

Crom's most durable product, which he realised in the early 1950s, became known
as the Crom System, and in 1952 he was the co-founder with his son, Theodore R. 
Crom, of The Crom Corporation, Gainesville, Fla., and he was vice-president 
of the corporation until he sold his interest in 1957 and retired.  The Crom 
System became widely accepted because of its watertigbtness, economy of 
construction, and favorable appearance. 

Crom held more than forty patents, and one of the earliest was that for an 
automatic baseball machine, a game that continued to be used in amusement areas.
Among his later patents of importance were the method and apparatus for banding
tanks with high-strength wire (Pat. No. 2,858,048; 1958), which described a new
apparatus that came into wide use; and a method of making a liquid-impervious 
wall (Pat. No. 3,120,047; 1964), which described composite-membrane tank walls.

Among his writings was the monograph "The Preload System of Concrete Construction
with Special Consideration of Oil and Water Tanks and Pressure" (1935), the first
publication in circular prestressing of concrete.  Later papers were "Prestressed
Reinforcement for Domed Concrete Tanks" (Eng. News Record, Apr. 1936), 
"High Stressed Wire in Concrete Tanks" (ibid., Dec. 1943), "Design of Prestressed
Tanks" (Amer. Soc. Civil Eng. Proc., 1950), and "Design of Prestressed Tanks"
(Amer. Soc. Civil Eng. Trans., 1952).  

In 1918, during the First World War, he worked for the U.S. government as 
a civil engineer in Nitro, W. Va.  He was a member of the American Society 
of Civil Engineers, Tau Beta Pi, and Beta Theta Pi.  In politics he was 
a Republican.  His special interests included golfing, shooting, and baseball.
He was married in the State of Washington in 1914 to Bonnie Ethyl Newcomb and 
had two sons: John Maurice, who married Norine Garvey; and Theodore R., who 
married Wynona Inza Nitz.  John M. Crom died in Hawthorne, Fla., Feb. 6, 1977.

Page 93 has a picture of him, but I didn't make a copy of it.