Further, Koehler noted in his official report, the grain of the bottom uprights “matched end to end, showing that they had been cut from a single strip more than 13 feet long, likely the standard 14-foot length for lumber coming from the mill.”
The rails in the middle section, 14 and 15, were the same length as those in the first section, but were Douglas fir, grown largely in the Rocky Mountain west. It had become common in eastern markets, though.
Koehler knew this was not decorative wood. This was practical wood.
“Both the pine and the Douglas fir uprights were so-called 1-by-4-inch stock, mill-dressed, of the type of material commonly used for crating, and in the big cities, for underflooring,” he said.
During its late-May 1932 inspection of the ladder, the Bureau of Soil in Washington had found that Number 14 had a large spot of red iron oxide roof paint on it. To Koehler, that meant it had possibly been used as scaffolding or for some other construction purpose.
The rails on the top section proved “a study.” Number 17, on the top right, he identified as Douglas fir like the rails in the section beneath it.
Number 16 on the top left, though, was different from the other five rails “in very striking respects.” Like Rails 12 and 13 it was North Carolina pine, but Rail 16 was a more knotty type of lumber than the others. And there were other major differences to indicate it had not come from the same tree that produced the others.
First of all, it had not been machine planed like the others, but was hand-planed on both edges. That suggested to Koehler that it had been worked down from a wider piece of wood. It was also slightly narrower than the other rails.
“Why he planed both edges of rail 16 is a mystery unless it was rough edged to begin with,” he said in his report to Captain Lamb and Colonel Schwarzkopf. “The edges were not always at right angles to the face, and scratches made by the plane wobbled back and forth along the edge. . . . the scratches left by a hand plane on both edges of this rail were exactly the same as those on one side of each of the [cleats], proving conclusively that they were made by the same plane, and presumably at approximately the same time, probably when the ladder was made.”
He came to that conclusion because “a plane would hardly show the same pattern due to dullness for a number of years.”
Rail 16 also contained four nail holes made previously by square-cut or 8-penny nails made of iron. They had been in use since the early nineteenth century but had been phased out at the end of the 1800s as it became much cheaper to make round wire nails from soft steel. By 1913, 90 percent of nails made were wire nails. Square-cut nails were still used in some home constructions, however.
The spacing of the nail holes indicated the board and the nails had come from a “building of some kind.”
Now, two of the Douglas fir rails had a few irregularly spaced round wire nail holes in them as well, leading him to surmise these pieces of wood, too, had been used before, but their randomness of placement gave no suggestion as to what they had been used for. Rail 15 had one wire-nail hole near the top, one near the middle, and one near the bottom, all driven from the left side of the rail. Rail 17 showed one wire nail hole near its lower end and two in its middle.
A couple of the nail holes showed evidence of rust on the inside, but it was impossible to know if that was from using rusty nails, or because the wood had gotten wet, or because the silver nitrate used to find fingerprints on the ladder had gotten into the holes. Koehler didn’t have time at that moment to dissect the wood around the holes for further inspection, and he wasn’t sure if he did that he’d find something more. The fact that most of the nail holes did not have discoloration in them indicated the wood hadn’t been exposed to nature after it was logged.
The nails in Rail 16, though, were more “significant.” None showed signs of discoloration or rust around the heads and around the nail holes, telling Koehler definitively that the original “board had been nailed in a place sheltered from the weather.” Specifically, he believed it had come from a “protected location inside a building.”
He speculated it came from “the interior of a crude building, possibly an attic, shop, warehouse or barn.”
“Although cut nails do not rust as easily as wire nails,” he concluded, “if the wood had been nailed down outdoors in the early days when cut nails were commonly used, and had been exposed to the weather since then, there should have been considerable rust and discoloration around the nails.”
Further, he believed “the boards were pried off whatever they were fastened to and the nails were driven out from the back side. There were faint indentations near the nail holes on the back sides as if a pry had been used, although the impressions are faint, indicating that the nails were easily pulled.”
Moving on to the cleats, or rungs, Numbers 1 through 10, they were made of a soft wood, Ponderosa pine, or California white pine, as it used to be called. Number 11, the topmost rung, was Douglas fir.
Numbers 1 through 8, when placed together end to end into two strips of four each, “could be matched together sufficiently well so that there is no doubt that they were made from one board cut in two lengthwise,” according to Koehler. That said, they didn’t match sidewise perfectly, measuring about 5½ inches in width when the standard width of dressed lumber is 6½ inches. Even though there was an inch of wood missing between them, Koehler was convinced they had come from the same tree as their outer edges, when matched together sidewise, were perfectly square.
The inner edges of Numbers 1 through 8 were planed with the same hand plane that had worked on Rail 16. The ridges or scratches the planer left were distinctive.
Numbers 9 and 10 did not match up with Numbers 1 through 8, either endwise or sidewise, but they did match together quite nicely. They, too, had the same planer marks as Numbers 1 through 8 and Rail 16.
The ends of Numbers 1 through 10 had all been cut with a saw that did not leave coarse saw marks or break out the wood on the far side. “A fine saw,” Koehler deduced and said the sawing seemed to have been done at a 45-degree angle, indicating it was at table or workbench height when it was sawed.
Number 11 was the odd one of the rungs, coming from Douglas fir but not appearing to match the ends of any of the three Douglas fir rails (Rails 14, 15, and 17). There was nothing particularly distinctive about it.
None of the rungs showed any appreciable signs of wear. They weren’t worn down from painters or home builders or apple pickers climbing on them. According to Koehler, the evidence indicated that the ladder “had received no previous usage.”
In essence, he was reinforcing what authorities already suspected: the ladder had been built specifically for this crime.
The dowels, or pins, used to connect the ladder sections, Numbers 18 and 19, were birch, likely white birch found in the Northeast. They were 1 foot, 3¾ inches long and 1 foot, 2 inches long, respectively. The growth rings didn’t show perfect matching, so there was no evidence they came from the same piece of wood.
Both showed faint spiral marks from a lathe and were covered with something like linseed oil, but dirt had gotten into the pores to make that identification difficult. Koehler believed “their fair but not perfect smoothness and thin coating indicate that they were made for a semi-refined purpose, where they would be handled but would not be used for an ornament.”
He thought maybe they had come from the handle of a toy rake or a small broom.
Koehler also inspected the chisel found near the ladder. The chisel used to make the mortises for the ladder cleats had been sharp, sharper than the hand plane for sure, and Koehler reported that it had cut the wood smoothly along the grain with no scratches. He said it was not possible to determine the width of the chisel used in building the ladder. He initially did not try to compare the chisel found at the scene with the chisel used in the construction of the ladder, but its impact left an impression nonetheless.
Authorities also wondered if the chisel could have been used as the blunt instrument causing the hole in the skull of Charles Lindbergh Jr.
“For all my cold and calculating science,” Koehler later said. “I could not touch it without a sense of horror.”
On March 4, 1933, he turned in his thirteen-page report and some diagrams to support his assertions. Schwarzkopf and Lamb immediately devised a plan of action and implemented it two days later.
“An obvious thing to do was to make a canvass of territory adjacent to the Lindbergh home to see what house, yard or scrap pile might have furnished the kind or kinds of lumber found in the ladder,” Koehler said. “Since the kidnapper appeared to have been sufficiently familiar with the place to know where the nursery was located, the possibility that some of the workmen or others living in the vicinity might have taken lumber for the ladder from the premises and committed the crime was not to be overlooked.”
The New Jersey State Police detectives who went with him were Nuncio “Nick” DeGaetano and Lewis Bornmann. Both had been promoted from trooper to detective four months after the kidnapping. DeGaetano had been one of the first officers to arrive at the crime scene that night and had discovered the footprint under the nursery window. More importantly to Koehler, Bornmann was the detective who had found the ladder several yards away from the house.
Koehler was a scientist, used to taking detailed notes. And as a government scientist, he was painstaking in chronicling in his daily reports his every move when he wasn’t in his Madison laboratory. As he drove up the long road to the home, Koehler realized this was not a time to sightsee or to be awestruck. He would inspect all of the woodwork in the home, from the basement to the attic.
There was no Ponderosa pine and only some North Carolina pine of a wider stock found in concrete forming, attic floor, and roof boards. It didn’t match anything in the ladder. The three men didn’t find any Douglas fir, either. They took slivers off the back of some enameled interior trim in the home’s library, because Squire Johnson had earlier said it matched what he believed to be the maple wood in the dowels.
Johnson was wrong on both counts. The dowels were birch. And Koehler’s microscope helped determine that the wood from inside the library was yellow poplar.
On that first day in the field, they found a birch dowel at an old deserted stone house in the Lindbergh neighborhood and would take it to headquarters. More exciting for Koehler, they went to the home of neighbor Charles Schippel, who wasn’t there to let them in. Instead of waiting, Bornmann boosted Koehler by the foot and they got in through a window.
“I was just like a burglar,” he said later.
Schippel had remodeled his home within the last year or two, which was obvious because he had unpainted lumber exposed to the weather and it showed no signs of wear. Koehler and the detectives took shavings from a piece of wood with red paint on it to analyze back at Troop C Headquarters because Rail 14 had red paint on it.
“Surprisingly primitive places were visited,” he said later about their investigation. “A condition of living existed in some of the hill country that one would associate with the less accessible valleys of the Appalachians rather than with a country only 50 miles from New York City and 40 miles from Philadelphia.”
The next day, they went back to the Lindbergh house to look at the old “Gate house” and “Chicken house” at the entrance of the property and the garage, where they found an old hand plane said to belong to the superintendent during construction of the Hopewell home. Koehler tried it on some soft pine nearby, and the markings didn’t match those on the ladder.
They also inspected the pile of waste wood left over from the construction of the home. Again, they found no clues.
They went to nearby Princeton, New Jersey, to speak with George Matthews, a contractor on the Lindbergh home, to see if any Ponderosa pine had been used in its construction. Matthews said it had not.
They traveled to the nearby Miller and Sons lumber yard to ask about the use of North Carolina pine, Ponderosa pine, and Douglas fir in that area. They went to Trenton to ask the Updike-Kennedy Company folks the same questions and found out the North Carolina pine was “used for crating by the potteries.”
Koehler, Bornmann, and DeGaetano spent the next two days visiting nearly a dozen lumber yards in New Jersey near New York and in Staten Island. Few outlets were using Douglas fir. More had Ponderosa pine, but nothing matching the marks on the ladder. Repeatedly they heard that North Carolina pine was not used in Jersey but was found in subfloors and concrete forming in New York City and Brooklyn.
So that’s where they went next.
On March 10, Bornmann and Koehler drove to New York City. Their first stop at 74 Greene Street, at Olney & Warren’s, who manufactured planing mill machinery, brought nothing but derision.
“We were given rather casual attention,” Koehler reported, “with off hand remarks that there would be no chance of tracing the peculiar marks on the edge of the N.C. pine used in the bottom rails of the ladder.”
Then, they went to the Production Machinery Sales Company, 52 Vanderbilt Avenue, which sold woodworking machinery. There they were told the marks on Rails 12 and 13 were “due to a bolt on the cutter projecting beyond the knives, or to some sharp projection on the guides, but that those things might occur on any planer and could not be traced to any particular make or type of machine.”
On to the Berst-Forster-Dixfield company, 1602 Craybar Building, which distributed dowels. While the people they spoke to were very courteous, they offered little productive information.
The pattern continued. They heard that Douglas fir was not normally used in New York and the vicinity, but maybe in crating or bulkheading in freight cars.
Despite the dead ends, Schwarzkopf was pleased with his new wood expert and the leads he was pursuing. He sent Carlisle Winslow a telegram: “Request permission for Mr. Koehler to continue investigation for week longer stop thanks for cooperation.”
Winslow responded that that was “satisfactory” before issuing a gentle reminder. “Assume you will continue to cover his expenses,” his return Western Union telegram stated.
First thing the next morning, Saturday, Koehler and Bornmann met with H. C. Padon of the Yates-American Machine Company at 405 Lexington Avenue in New York City. Yates-American was one of the largest manufacturers of planers in the country. Padon believed the peculiar markings “might possibly be due to a chip being firmly lodged between one of the knives and the block of the cutterhead, or to a projection on the guide.” Worse for the detective and the scientist, he thought that “it might occur on any type or make of planer.”
From there, they headed down to the docks, visiting first a wood products company that supplied boat builders and then three more outfitters. They had no luck finding ¾-inch birch dowels on the water.
So then Koehler went to a number of hardware shops and stores that had household articles on display in lower Manhattan. He was trying to prove his theory that the ladder pins were made from some type of handle. He spent the afternoon at large retail stores, ostensibly to find ¾-inch dowels, and was successful. At Wanamakers, they were used in painted toy broom handles and in apparently shellacked long dustpan handles. Macy’s also had the painted toy broom handles, plus mop and dustpan handles with a transparent coating on them. Woolworths, opposite Macy’s, had toilet brushes with painted and uncoated ¾-inch handles.
The team took Sunday off before heading to Philadelphia on Monday. During a stop at the Sears, Roebuck plant there they found rugs rolled on bamboo sticks, oil cloth on a hollow cardboard core, and toy broom handles made of conifer, not birch. They searched the toy, kitchen, sporting goods, and hardware departments but found nothing.
The Pennsylvania Lumbermen’s Association allowed them to attend a meeting of its members where they inquired about North Carolina pine and Rail 13. The association’s members looked
at the evidence and said that “it might be used for many purposes, including trim.” They thought it came from farther south than North Carolina, perhaps Georgia. They were surprised it had been dressed to 3⅝ inches and not the more common 3¾-inch width.
At another toy maker, Heintz Manufacturing on Front and Olney Streets, they discovered that the company’s toy garden sets used to use ¾-inch birch dowels had been turned over to another company.
Back they headed to New Jersey and more meetings with lumber companies, one of which suggested that the source or outlet for the North Carolina pine might “be traced through wholesalers, as they keep a record of sales for several years back.”
On the morning of March 15, Koehler went through the left door at the mess hall into Schwarzkopf’s private dining room, where he met with Captain Lamb, Lieutenant Keaten, a federal Department of Justice agent, and other New Jersey State Police officers. Koehler briefed them on what he knew and, more importantly, what he thought they could learn.
“Good police work and science are similar,” he once said. “Both are investigative in nature and usually entail much legwork and drudgery.”
This case appeared to be no exception. Schwarzkopf, with no other viable leads to pursue, asked Koehler to continue and sent Winslow in Madison a long note explaining why he needed to keep the country’s top wood scientist on the case—indefinitely. He told Winslow that Koehler was “making progress,” and that meant “more angles to be looked into and investigated. He continued,
The Sixteenth Rail Page 9