(1)Thatcher's troubles pile up like London's snow. (2)Growing chorus of critics lash out at 'Iron Lady's' strict economic policies

What do a checked cloth cap, a patrician accent reverberating from a lofty ceiling, a ''Gang of 14,'' a train that leans around corners, and the worst blizzard for 14 years, have in common?

Answer: Each in its own way adds up to more pressure on, and criticism of, the Conservative government of Margaret Thatcher.

These are hard days for the ''Iron Lady.'' She battles to restore Britain's economy and her party's own political fortunes against a growing chorus of critics, including those of her own party. Her mood remains defiant in public. In fact, she has already shifted economic ground - but her critics only demand more.

She could still win the next general election two years from now - but it is hard to find a forecaster these days willing to predict it.

The checked cloth cap is tilted rakishly forward on the head of Britain's newest and in some ways its most crucial trade union leader just now, ''King Arthur'' Scargil of Yorkshire.

Britain's National Union of Miners (NUM) have sent a sharp signal to Mrs. Thatcher by electing the radical left-wing Mr. Scargill to its top post with an overwhelming 70.3 percent of a secret coalworkers poll. Eighty percent of miners took part.

At the same time, NUM leaders briskly rejected a 9.1 percent pay increase offer by the government's National Coal Board. Even moderate miners are said to be pressing now for a minimum of 12 percent.

The sight of Mr. Scargill, cloth cap in place arriving for pay talks after his election, is far from cheering for Mrs. Thatcher, who wants to restrict public employees to pay raises of 4 percent this time. ''King Arthur'' noted for his extreme leftist view, takes over his union from moderate Joe Gormley in four months time.

At this writing, the NUM was headed toward another coalworkers' ballot on whether to strike. Fifty-five percent is required before a strike can be called.

Meanwhile, Mr. Scargill has appeared on il5l,0,24l,7p3British TV screens and radio programs saying the NUM could be more radical now.

He has long campaigned for a four-day work week for miners, retirement at age 55 on full pay, and other benefits. The British people in the past have shown considerable sympathy for miners and their difficult, dirty work.

The patrician accent belonged to the same Edward Heath, who is now increasingly in the headlines after his defeat in 1974. He has held no formal office under Mrs. Thatcher, and his distaste for her leadership is an open secret. He clearly senses Mrs. Thatcher's political weakness just now. Recently he hinted he might be prepared to work with the new Social Democratic-Liberal alliance in a new government.

Now he has risen to his feet in a House of Commons debate on the latest minibudget by Chancellor of the Exchequer Sir Geoffrey Howe to criticize heavily what remains of Mrs. Thatcher's monetarist policies.

There never was an intellectual justification for pure monetarism, nor was there any practical justification for it, the former prime minister said, thus attacking the root of the Thatcher economic policies so far. Mr. Heath also heartened backbenchers, led by former Cabinet minister Sir Ian Gilmour, whose own aristocratic tones have been rising in protest against the government. All want more help for business, and an end to the payroll tax.

Many observers predict tax cuts in the spring. This may not be enough for critics.

Broadly, the Gang of 14 (as well as the Labour Party and the Social Democratic-Liberal alliance) want more government spending to boost the economy (''reflation'' to use the technical jargon.)

Labour points out that even government theoreticians have admitted that letting the sterling exchange rate rise last year was a mistake. Shirley Williams, a leader of the Social Democrats, wants (STR)5 billion to (STR)6 billion of government money to be spent each year to modernize housing, electrify the railroads, streamline harbors and other transport, and reequip small and medium business.

The government's effort to solve one transport crisis ran into trouble itself when the much-heralded Advanced Passenger Train broke down twice on its first two days of public testing between Glasgow and London.And the worst blizzard for 14 years led to new public complaints that weather forecasters, were taken by surprise, thus placing more blame on the government.