As a captain of industry and the richest man in America, William H. Gates has often been compared to industrial titans of the past.

And just as the railroad tycoons of the 1800's set the gauge for the nation's railroad tracks, Mr. Gates's Microsoft Corporation seems intent, its critics say, on the modern-day equivalent: controlling many of the basic technical specifications of the global Internet.

The result could be a rapid end to the furious pace of entrepreneurial innovation that has marked the Internet in recent years, critics say, just as hegemony of Microsoft's Windows software has often been blamed for limiting technical innovation in personal computing.

Lately, there has been much publicity for Microsoft's new-found focus on the Internet, starting with a celebrated speech last December in which Mr. Gates said his company would cooperatively "embrace and extend" industrywide Internet technical standards. The public spotlight has focused on new software features and product release dates, as the company tries to catch up with Internet leaders -- like the Netscape Communications Corporation, maker of the Navigator browser for the World Wide Web, and Sun Microsystems Inc., whose Java software is designed to move computing power onto the network from the desktop -- that have been seen as the biggest threat in years to Microsoft.

But while these well-chronicled contests continue, far more meaningful skirmishes are occurring among little-known industry groups that set the arcane -- but crucial -- technical specifications that determine whether and how well various makes and models of hardware and software can work together on the Internet.

On this front, Microsoft may be in the best position to use its market power to influence technology's future. And it is a measure of Microsoft's intensity that one of these struggles has even placed the company at odds with its symbiotic hardware partner, the Intel Corporation.

Rather than merely embrace and extend the Internet, the company's critics now fear, Microsoft intends to engulf it.

Microsoft executives insist that the company intends to cooperate with Internet standards groups. But according to industry executives who have observed Microsoft's activities in these standards sessions, there is evidence that the company is attempting to employ the same sort of business practices that helped it rise to dominance in the personal computing industry -- and that have repeatedly drawn the scrutiny of Federal antitrust investigators.

Just as Microsoft did with PC technology, these executives fear, the company intends to subsume more and more of the Internet's basic technology in Windows.

Indeed, even while it works behind the scenes to shape future technical standards to its competitive advantage, Microsoft has begun to absorb into Windows various Internet capabilities -- like the company's Explorer browser for the World Wide Web and Front Page set of tools for creating Web pages. By offering such products as part of Windows, critics contend, Microsoft could wage an Internet war of attrition against rivals large and small -- whether ascendant powers like Netscape or established tool makers like Adobe Systems Inc., producer of Web-page designing software called Pagemill.

"There are societal consequences to Microsoft's strategy," said Gary Reback, a Silicon Valley lawyer who has battled Microsoft in court and before the Justice Department in recent years on behalf of a number of its competitors. "Here is a new technology and a whole new wave of commerce, and Microsoft wants to suck it in to the operating system to maintain its monopoly."

Microsoft insists that using the Windows vacuum cleaner as a way to suck away revenue from competitors is simply good business.

"Yes, that is our business strategy," said Paul Maritz, the executive vice president for the company's Internet business. "But not out of spite. What you're seeing here is competition, which is good and healthy. Now we have Netscape's Navigator and Sun's Javasoft as our new competitors."

Mr. Reback, though, has been trying to raise alarms with the Justice Department, which last year was intensely investigating the potential antitrust implications of Microsoft's placing an icon for its on-line Microsoft Network on the main screen of Windows 95.

Justice officials decline to comment, but as Microsoft has turned its focus from subscriber-based on-line services to the more open Internet and World Wide Web, the antitrust investigation has reportedly become moribund -- though it is not officially closed.

Not all legal experts, however, see an antitrust threat in Microsoft's Internet activities.

"Maybe it's not a polite way of doing business, but it's not Microsoft's responsibility to be polite," said William F. Baxter, a Stanford law professor who headed the Justice Department's antitrust division for three years in the Reagan Administration.

Still, many companies have grown wary of Microsoft's intentions since it set its sites on the Internet.

On Dec. 7, the same day that Mr. Gates was delivering his embrace and extend" speech at Microsoft headquarters in Redmond, Wash., a small group of software developers from Intel was meeting in Silicon Valley with Microsoft counterparts. The group was trying to hammer out details of a new technical standard designed to improve and streamline all aspects of computer security and privacy on the Internet, regardless of the brand of hardware or software used.

For five months, Intel had been quietly orchestrating this effort, which had the preliminary support of a group of influential companies that included Netscape and Sun Microsystems. Apple Computer Inc. was also considering coming aboard. But while Microsoft's commitment looked increasingly likely, it was still not certain.