Carriage and Car

My search on Ngram looked at the use of 'carriage' and 'car'. As expected 'carriage' initially is presented as more frequent, before 'car' takes over and becomes the new norm. The use of 'car' begins a quite steep increase beginning around the 1880s, crossing 'carriage' at 1905. The use of 'carriage' it appears, remained relatively steady until around 1903. Sadly my transport knowledge is not brilliant however, this would suggest that during the early 1900s a particular shift occured from 'carriage' to 'car'.