  With over 100 years of solar observations, the Kodaikanal Solar Observatory
(KoSO) is a one-of-a-kind solar data repository in the world. Among its many
data catalogues, the `suncharts' at KoSO are of particular interest. These
Suncharts (1904-2020) are coloured drawings of different solar features, such
as sunspots, plages, filaments, and prominences, made on papers with a
Stonyhurst latitude-longitude grid etched on them. In this paper, we analyze
this unique data by first digitizing each suncharts using an industry-standard
scanner and saving those digital images in high-resolution `.tif' format. We
then examine the Cycle~19 and Cycle~20 data (two of the strongest cycles of the
last century) with the aim of detecting filaments. To this end, we employed
`k-means clustering' method and obtained different filament parameters such as
position, tilt angle, length, and area. Our results show that filament length
(and area) increases with latitude and the pole-ward migration is clearly
dominated by a particular tilt sign. Lastly, we cross-verified our findings
with results from KoSO digitized photographic plate database for the
overlapping time period and obtained a good agreement between them. This work,
acting as a proof-of-the-concept, will kick-start new efforts to effectively
use the entire hand-drawn series of multi-feature, full-disk solar data and
enable researchers to extract new sciences, such as the generation of pseudo
magnetograms for the last 100 years.
