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While the tools available for probing the Milky Way's internal structure are diverse, none has especially high three-dimensional resolution over wide areas. To address this problem, \citet{Goodman_2014} recently suggested that extraordinarily elongated filamentary infrared dark clouds, termed "bones" could be used to determine the structure of the Milky Way's spiral arms, their location within the Galaxy, and their appearance as viewed by an outside observer. \citet{Goodman_2014} presented Nessie as the first "bone" of the Milky Way. They found that Nessie was at least three degrees ($\sim 140$ pc), and possibly as long as eight degrees ($\sim 450$ pc) in length, while being less than 0.1 deg ($\sim 0.6$ pc) wide. They also conclude that Nessie lies very near the geometric mid-plane of the Milky Way Galaxy, at the 3.1 kpc distance to the Scutum-Centaurus arm. An analysis of the radial velocities of ${\rm NH}_3$ emission and CO emission confirms that Nessie runs along the Scutum-Centaurus arm in {\it p-p-v} space, suggesting it forms a dense spine of that arm in physical space as well \citep{Goodman_2014}  Until very recently, no simulations had the spatial resolution to predict that super-dense filaments should trace the middle of spiral arms. In 2014, numerical simulations from \citet{Smith_2014}, using the AREPO moving mesh code, revealed dense filaments, with aspect ratios and column densities similar to Nessie {\citep[cf.]{Goodman_2014}, \citep[cf.]{Goodman_2014},  forming within and parallel to the mean plane of a simulated spiral galaxy. A detailed analysis of Nessie's properties, along with these new simulation results, suggests that Nessie may be the first in a class of objects that could trace our Galaxy's densest spiral features. It is gratifying to recognize that Nessie should be the easiest object of its kind to find. Nessie is located in the closest major spiral arm to the the Sun, perpendicular to our line of sight yet slightly offset from the Galactic center. This placement means that Nessie will be clearly visible against the bright background of the Galactic center, and it will appear more elongated than objects more distant or tangential to our line-of-sight. Making use of both large scale mid-infrared surveys and molecular spectral line maps, we search for harder-to-find bones, characterize their key properties, and begin to establish their relationship to the Milky Way's spiral structure. When used in conjunction with the kinematic, parallactic, and extinction data outlined above, these new bones have the potential to pin down the Milky Way's galactic structure, improving the level of detail from tens of parsecs to around one parsec in regions near bones.