They merely show that, in the conditions of the particular experiments, the thermodynamic equilibrium value of the osmotic pressure cannot be reached - the thermodynamic or theoretical osmotic pressure (which must be independent of the nature of the membrane provided it is truly semi-permeable) is a different thing from the equilibrium pressure actually reached in a given experiment, which measures the balance of ingress and egress of solvent through an imperfect semi-permeable membrane.
The action of sandstone in filtering salt waters was investigated in 1878 by Dr Isaac Roberts, F.R.S., who showed that when salt water was allowed to percolate blocks of sandstone, the effluent was at first nearly fresh, the salt being filtered out and crystallized for the most part near the surface of ingress to the sandstone.
A flow pipe which serves also for expansion is taken from the top of the cylinder to a point above the cold - water supply and turned down to prevent the ingress of dirt.
While seated with his family and friends absorbed in the play, John Wilkes Booth, an actor, who with others had prepared a plot to assassinate the several heads of government, went into the little corridor leading to the upper stage-box, and secured it against ingress by a wooden bar.
In laying out the approaches and station yard of a passenger station ample width and space should be provided, with welldefined means of ingress and egress to facilitate the Passenger ci rculation of vehicles and with a long setting-down stations.
The particular site of Immingham was chosen because the deep-water channel of the Humber, which lower down runs midway between the shores, here makes an inward sweep and leads right to the dock gates, thus obviating much initial dredging, providing ingress and egress at any state of the tide, and rendering the towage of the vessels unnecessary.
The application of vestibules is practically limited to trains making long journeys, as it is an obstruction to the free ingress and egress of passengers on local trains that make frequent stops.
For some way beyond the only seaport is Bosa, which has only an open roadstead; and at the southern extremity of the Nurra come the Gulf of Alghero and the Porto Conte to the W., the latter a fine natural harbour but not easy of ingress or egress.
For three months during each year business was suspended, and all ingress or egress except for the most necessary purposes was forbidden.
This, together with the compactness of the mortar, hinders the ingress and egress of water, and prevents the dissolution and ultimate destruction of the cement.