One cause which acts permanently in differentiating the times of selling, and thus the periods of turnover in general, is the distance of the market in which a commodity is sold from its place of production. During the entire trip to the market, capital finds itself fettered in the state of commodity-capital. If goods are made to order, up to the time of delivery; if they are not made to order, there must be added to the time of the trip to the market the time during which the goods are in the market waiting to be sold. The improvement of the means of communication and transportation cuts down absolutely the wandering period of the commodities but does not eliminate the relative difference in the time of circulation of different commodity-capitals arising from their peregrinations, nor that of different portions of the same commodity-capital which migrate to different markets. For instance the improved sailing vessels and steamships, which shorten travelling, do so equally for near and distant ports. The relative difference remains, although often diminished. But the relative difference may be shifted about by the development of the means of transportation and communication in a way that does not correspond to the geographical distances. For instance a railway which leads from a place of production to an inland centre of population may relatively or absolutely lengthen the distance to a nearer inland point not connected by rail, as compared to the one which geographically is more remote. In the same way the same circumstances may alter the relative distance of places of production from the larger markets, which explains the deterioration of old and the rise of new centres of production because of changes in communication and transportation facilities. (To this must be added the circumstances that long hauls are relatively cheaper than short ones.) Moreover with the development of transport facilities not only is the velocity of movement in space accelerated and thereby the geographic distance shortened in terms of time. Not only is there a development of the mass of communication facilities so that for instance many vessels sail simultaneously for the same port, or several trains travel simultaneously on different railways between the same two points, but freight vessels may clear on consecutive days of the same week from Liverpool for New York, or goods trains may start at different hours of the same day from Manchester to London. True, the absolute velocity — hence this part of the time of circulation — is not altered by this latter circumstance, a certain definite capacity of the means of transportation being given. But successive shipments of commodities can start their passage at shorter intervals of time and thus reach the market one after another without accumulating in large quantities as potential commodity-capital before actual shipment. Hence the return of capital likewise is distributed over shorter successive periods of time, so that a part is continually transformed into money-capital, while the other circulates as commodity-capital. By spreading the return over several successive periods the total time of circulation and hence also the turnover are abridged. The first to increase is the frequency with which the means of transportation function, for instance the number of railway trains, as existing places of production produce more, become greater centres of production. The development tends in the direction of the already existing market, that is to say, towards the great centres of production and population, towards ports of exports, etc. On the other hand these particularly great traffic facilities and the resultant acceleration of the capital turnover (since it is conditional on the time of circulation) give rise to quicker concentration of both the centres of production and the markets. Along with this concentration of masses of men and capital thus accelerated at certain points, there is the concentration of these masses of capital in the hands of a few. Simultaneously one may note again a shifting and relocation of places of production and of markets as a result of the changes in their relative positions caused by the transformations in transport facilities. A place of production which once had a special advantage by being located on some highway or canal may now find itself relegated to a single side-track, which runs trains only at a relatively long intervals, while another place, which formerly was remote from the main arteries of traffic, may now be situated at the junction of several railways. This second locality is on the upgrade, the former on the downgrade. Changes in the means of transportation thus engender local differences in the time of circulation of commodities, in the opportunity to buy, sell, etc., or an already existing local differentiation is distributed differently. The importance of this circumstance for the turnover of capital is evidenced by the wrangling of the commercial and industrial representatives of the various localities with the railway managements. (See for instance the above-quoted Bluebook of the Railway Committee. [See p. 154 of this book. — Ed.] )