When you call Orlo Nichols for complicated information about Social Security statistics and cost ratios, you are impressed at his grasp of all facts and figures.

Nichols is an actuary with the Social Security Administration in Baltimore, and he deals with complex mathematical formulas and massive tables of numbers. Over the phone he rattles them off like machine-gun bullets, with remarks like "Look at line 3 of table I, ratio 1.49 to 1."

Nichols' ability to skip rapidly from one table to another is even more impressive when you learn that he is blind - and has been for the entire 37 years of his life.

He is the first blind person to be successfully employed as an actuary - a job the average person would assume requires a person with sight.

Not so, said Nichols in an interview in his office. "It is possible for a blind person to do work like this. You don't have to be exceptional to achieve."

Nichols uses a variety of machines - some of which he learned to operate as a child in upstate New York - to "see" the figures, tables and calculations needed for long-range projections on the costs of Social Security and insurance.

He has already demonstrated his capacity to handle the work by passing eight of the nine achievement exams given by the Society of Actuaries - and is to take the ninth and highest May 16 in Baltimore. They prepare the questions for him specially in braille (raised symbols); he dictates the answers to the multiple-choice part and answers the essay questions on a typewriter.

In his office, Nichols demonstrated the devices he uses to do his work.

One of the most remarkable machines is an Optacon (Optical to Tactile Converter). It weighs about three or four pounds and looks like a small portable tape recorder with a miniature microphone attached by an electric cord.

The difference is that the "microphone" is actually a tiny electric-eye camera. It scans a page of print and sends a signal to the machine which activate a system of vibrating pins on a flat panel inside the Optacon.

The pins form raised letters and numbers identical to the material on the page being scanned. By sticking his left hand into a slot on the machine and feeling the raised letters and numbers, Nichols is able to "read" what is on the page-or on the face of a calculator-and thereby "see" printed material accurately and rapidly.

"I think when I was talking to you on the phone about those tables a few weeks ago, I was using the Optacon," Nichols laughed. "But because I have worked with these particular tables so long, I also know some of it by heart."

Nichols said the Optacon has been available since about 1970 or 1971. "I've had mine since 1974.They now cost around $3,000."

Before the Optacon, Nichols used aides or colleagues with normal sight to read to him, as he still does sometimes, and a calculator with a braille face. But the new device has made it easier for him to "read" material by himself-even handwriting can be picked up on it. "But handwriting is not uniform enough for me to read it most of the time."

To write down material, Nichols has a variety of machines available to him. He can dictate into a recording machine and then a secretary can transcribe it-just as many persons with sight do. He learned to use a regular touch-typewriter at the age of 10. "Even when you aren't blind, they teach touch typing by telling you not to look at the keys."

He also uses a "braille-writer," which he also learned as a youth. It looks like an ordinary typewriter but it has only six keys which punch out raised-dot combinations on stiff cardboard to form the braille alphabet and numbers.

In his work, he programs computers a lot. "I write out the program steps in braille. Then I can punch out the program steps [on a normal keypunch] and feed it into the computer."

As a child, he learned numbers and did calculus, square roots and long division on a variety of machines suitable for use by the blind. The ancient abacus is one-and many blind still use it. Another device, called a "type slate," is a like a peg-board where calculations are made by position. Still another is a "cube slate" where there are cubes with braille numbers on all six faces.

Born in Cobleskill, N.Y. Nichols said, "I was always interested in math, since I was a very young child. I wanted my life to be something related to math. My sister was a librarian for an insurance company and I happened to hear about actuaries from her."

Until his senior year in high school, he went to a special school for the blind where he learned braille, math calculations and ordinary touch typing, among other things.

Then he attended public high school and after that Hamilton College in New York, and then did graduate work in actuarial science at Wisconsin University.

He got around using a cane-and no guide dog.

I was interviewing for jobs at the campus and insurance company representatives came in-they weren't really very interested at that time, 1967, in hiring a blind actuary.

"But Robert J. Myers, then chief actuary of Social Security, heard about me. He wrote me a letter and hired me as an actuary in 1967."

Nichols first worked in Washington, then was transferred to Baltimore Social Security headquarters where he is one of about three-dozen actuaries. His salary is in the mid-$20,000 range.

He has worked on the financial interchanges between the Railroad Retirement and Social Security systems (there is a very complicated system of cross-funding) and on ratios of benefits to payments for typical Social Security families. Myers, now a consultant here, called the latter study "excellent" and said Nichols is a "remarkable man."

Nichols' wife, Mary, is also blind and went to the same school he did. They have two adopted children with some visual loss. He gets to work by bus.

He says Myers is wrong-he is not really "remarkable" at all, just a man with a mathematical bent who is also blind.

"I hope something which gets across is that blind people are a lot like anyone else in that they have varying degrees of physical and mental capacity. Most of us are capable, not just a few exceptions. The real reason for doing an interview like this is the hope that someone like a potential employer of others will read this and say, 'It's possible for a blind person to do work like that.'" CAPTION: Picture, Working with Optacon, Nichols holds sensor in right hand and "reads" with left. By Linda Wheeler-The Washington Post