Pontoon Crossing; 1941
Above, a wireline conveyed bailer on this large cable too rig is being run in the hole, down either surface or intermediate casing. The driller will mark the wire line, pick up and drop the bailer several times until he believes it is full. It may take several clean up trips before drilling can resume. Below the rig floor is likely some form of full opening control valve and the 1 1/2 inch line with a gate valve seen turned down into the cellar, at the feet of the driller, is probably a fill up line. 
In this photo above the bailer is coming thru the floor. The dump bucket, or dump pot behind the bailer drains to the reserve pit. Depending on depth of the well some cursory observations will be made by the driller, and written down in his log, about the nature of the cuttings bailed from the well.
Hung back in the derrick, behind the floor hand, is the bit and X-over subs that comprise the BHA. On the rack is not drill pipe but another drill collar to add to the BHA for additional weight. In percussion drilling, weight is beneficial; its good for rate of penetration and helps reduce deviation from vertical. 
Both of the photographs, above, reference the term 'Pontoon Crossing.' The mesas in the background give insight into where this well might have actually been drilled (I've been there) and that too is of great significance in early West Texas history. 
Along the Emigrant and Overland Trails that led Anglo-Americans to the west there were few places to cross the Pecos River in West Texas. The river was known for its steep embankments, deep, fast water in rainy periods and was often prone to flash flooding... of walls of water coming down on wagon trains from seemingly nowhere. A shallow, narrow riffle known as Horsehead Crossing was used to ford the river beginning in the early 1800's; it was located in Crane County and west northwest of what would eventually become the town on McCamey in Upton County.
Goodnight, Loving and Chisum all drove herds of cattle north toward the Llano Estacado and crossed the Pecos at Horsehead, as did Larry McMurtry's imaginary, Hat Creek Cattle Company in the epic film, Lonesome Dove.
The Pecos River often had a sulfur smell to it and the water was high in salinity. But the foul water was the only water for over 90 miles, east or west, and the banks of the stream were often lined with dead cattle and horses who drank themselves to death upon thirsty arrival. From the book, Crossing the Pecos by Patrick Daren:
The devil could dream such a damnable stream
As the Pecos River Southwest
From bank to bank she reeked and stank
Like a thousand buzzards nests.
The term, "Horsehead" was used for numerous horse skulls that hung in mesquite trees along the nearby trail leading to the crossing. Settlers traveling west along the Emigrants Trail were often slaughtered by Comanches at this river crossing. When the Comanches were vacationing in Mexico the Apaches would move in and slaughter more settlers and steal horses and mules. Horsehead Crossing was a forbidding place that actually smelled of death. Early travelers were glad to have it at their back.
Charles Goodnight once wrote of the land west of the Pecos River...
" It is the graveyard of a cowman's hopes."
Map of Horsehead Crossing, 1875; drawing by Captain S.T. Norvell.
By the 1820's a different crossing of the Pecos was found to the southeast and downstream of Horsehead, some 15 miles northwest of what would someday become the town of Irran. A sort of floating, barrel bridge was built there, across deeper water and more wide open spaces that made it harder for Indians to wait in ambush. The bridge was built by the US Army and Camp Melvin was erected to guard the crossing, eventually named Pontoon Crossing. This crossing became ideal for wagon trains and stage coach trips along the Old Spanish Trail from San Antonio to El Paso. 
After the Civil War a mail post and way-lay station was built at Pontoon Crossing It stayed in tact, this floating bridge, until nearly 1919 and there are surveyor monuments identified along the river that reference Pontoon Crossing. There is nothing there today, no roads into Pontoon Crossing, only remnants of old buildings and rock corral used to hold mules for the Army.
Left, part of the old mail post at the pontoon crossing across the Pecos, Crockett County. 
The land around the old floating bridge, on both sides of the river, was owned mostly by J.H. Tippet, who held over 80,000 acres in Pecos and Crockett Counties in the late 1880's and 90's. I believe the well in the photograph, above, is located on Tippet's old, "Punkin Division." The Texas GLO suggests that Roxanna, or Marland Oil might have been the operator of the well. There is a small Grayburg field in this area called Hanson Field, still on the Texas Railroad Commission proration schedule.
Down the Pecos River from the great Yates oil field, thru Terrell and Val Verde Counties in the Val Verde Basin, things get gassy and there is very little oil production. Sediments are very faulted and folded over each other, the geology very complex.
Difficulty in surveying the Pecos River in the early 1800's led to yet another awesome land vacancy dispute in the great, Yates Oil Field that I will get to someday, promise. Much like the Landreth vacancy in Crane County, it caused many chicken fights between greedy people trying to get their hands on LOTS of free royalty.
The Pecos River drainage basin through Pecos and Crockett Counties is beautiful, desolate country, even today. I have floated and walked this grand river several times on overnight trips, fishing with a 2 weight rod for Red Ear perch as big as sauce pans. It is, however, no country for weenie, city folks. You will be scratched, scraped, gored, poked bit, stuck and stung by pear, mesquite, cholla, blackbrush, snakes, leeches, ticks and scorpions; centipedes 8 inches long might crawl in your bed roll at night and light you up like downtown San Antonio. Best overlook those small inconveniences as that country does not tolerate a lot of whining.
The Pecos converges with the Rio Grande near Langtry, upstream of the beautiful, Devils River that also dumps into the Rio Grande. Though the Rio Grande River in Colorado and New Mexico often offers terrific dry fly fishing for trout, by the time the river passes thru Laredo it is full only of diapers and abandoned refrigerators.
The night sky along the Rio Pecos is as breathtaking as the Patagonia of Chile, or the Delta of Botswana, or the Great Slave Lake of the Northwest Territory of Canada and you will relish that the country you are in is land you love with all your being because it is...Texas.
The downstream reaches of the Pecos River.
God Bless Texas.
 The Dr. John Hill Collection, North Texas University Digital Photography Collection