The Tax Law of New Jersey states that, first, the true value of the real estate shall be ascertained; second, the true value of the tangible personal property; and the first law of 1884 stated: "and third, the value of the franchise"; but somebody discovered that there was something besides the value of the real estate, the tangible personal property, and the franchise. They did not know what it was, but there was something else; therefore, in the 1888 law they changed the third division of value to read: "the remaining property, including the franchise." As an example of one of the difficulties of determining classification, attention is directed to the term, Real Estate, which is broadly, but seldom accurately, understood. The Interstate Commerce Commission is the highest tribunal in the land, in the matter of railroad accounting, but it affords no help in many important elements of value; for instance, under the Interstate Commerce Commission, real estate includes only such real estate (land) as is not required for railroad purposes. All land actually used for railroad purposes is classified under "Right of Way and Station Grounds." When the engineers on the New Jersey valuation were sent into the field, it was necessary to specify exactly what elements must be described as real estate, and what as tangible personal property. The division line had to be defined accurately for the reason that all personal property is assessed permanently to the State, while, in the case of real estate, the State receives the taxes on a strip not exceeding 100 ft. in width, and the tax on all property used for railroad purposes outside this strip reverts to the taxing district wherein it is found. The vexatious question as to whether machinery is to be considered as real estate or personal property was settled by the New Jersey Law, which says that tangible personal property shall include all machinery; but it left unsettled the question: what is machinery? After careful consideration, real estate was divided into 74 classes, and all other tangible elements were classified as personal property. Some of the items of real estate are: ash-handling machinery and the like, chimneys, cisterns, conveyors, dams, locks, lock machinery, electric wiring, piping, heating, interlocking, signaling, pavements, reservoirs, shop fittings, tanks, telegraph lines, track, track scales, transfer tables, water-works, etc., etc. Generally speaking, all items of a fixed character were included in the 74 divisions of real estate. The difficulties of determining all the elements of real estate are mentioned simply to call attention to what at first glance seems quite simple, but on close examination is found to have great complexities. The question of useful life depreciation, direct and indirect, due to decrepitude or obsolescence, or both, is one of the illusive questions; and then comes the value of the franchise.