The Perfect Machine: Building the Palomar Telescope
by Ronald Florence

Book Review by Joe Orman

[Originally published in the newsletter of the East Valley Astronomy Club, April 2001]

If this were a work of fiction, a reader might dismiss it as being unbelievably fantastic.

• A factory casts the largest piece of glass ever made, only to discover after a 4-month cycle of annealing and cooling that the 200-inch diameter, 20-ton circular slab is flawed and must be completely re-done. During the 10-month cooling of the second piece, the factory floor is inundated by a flood, necessitating a frantic all-night effort with jackhammers and cranes to lift above the rising waters the huge transformers which power the furnace.
  
  
• The resulting colossal disk of glass is transported across the country on a train whose car and route are customized to admit the passage of such an immense object. Crowds across the country gather to see the crated cargo pass, with the awe and respect usually reserved for presidents.
  
  
• Five tons of glass is removed from the surface by grinding and polishing to achieve the required shape. The patient workers cannot see any result of their effort; only weekly optical tests show any progress. The final figuring is accomplished by individual rubs of a finger across the surface, then waiting for the distorting heat generated by that rub to dissipate. By the time the polishing is declared complete (having been interrupted by a world war), the glass has spent more than 11 years in the optics shop. The result is a surface so precise that its 200-inch span is accurate to within 2 millionths of an inch.
  
  
• On the day chosen to transport the glass to its mountaintop home, an unforecasted storm requires the transport trucks to negotiate the steep hairpin turns up the mountainside in pouring rain. The mammoth glass is then loaded into the pre-assembled observatory, completing its long journey without a scratch. The 12-story high dome rides on rails that were polished for 6 months, rotating so smoothly that visitors become disoriented -- swearing it is the building that rotates while the dome remains still.
  
  
• The surface of the glass is cleaned with Wildroot Cream Oil hair tonic, then coated with a layer of aluminum only a thousand atoms thick. The mechanism that supports and aims the resulting mirror is one of the largest structures ever machined. It is balanced so finely, and floated on an oil bearing so frictionless, that the entire 500 tons can be rotated by the weight of a single milk bottle.
  
  
• Through the depths of a great depression, individuals of wealth continue to finance all this ... a task unlike any that has ever been done before, will not be completed for years to come, and will result only in unforeseeable and intangible scientific progress. The project is planned and executed by a man whose body and mind are so affected by the stress that he has to take months off at a time to rest -- and dies before its completion.
  
  
• Twenty years after it was first funded, and only 9% over budget, the machine is finished -- the biggest of its kind in the world. The scientists that follow use its steady gaze to view a cosmos that had previously been beyond the reach of even their dreams.
  
  

But, incredibly, this is not fiction. All of these things really happened, in the construction of the 200-inch Hale Telescope which still operates atop Southern California's Palomar Mountain. Ronald Florence's The Perfect Machine is as thrilling as any adventure story, as engaging as any mystery novel, and contains as much pathos as any Shakespearean tragedy. It should be required reading for anyone planning a pilgrimage to the mountain, to stand in the presence of the great telescope itself. Florence's vivid account will not only give visitors an appreciation of the gigantic scale of the precision instrument, but also the unseen enormous quantities of money, labor, ingenuity and patience that went into its making. The world has known many larger telescopes since, but in terms of human effort overcoming adversity, indeed there has never been a more perfect machine.

A drawing by Russell W. Porter of the 200" Hale Telescope