HYDROCARBONS

Hydraulic Rams utilize the kinetic energy of a stream of water in a pipe to force a smaller quantity of water to a height greater than that of the head on the ram. The efficiency of this device is rather low, but its convenience, simplicity and the absence of moving parts (except valves), renders it quite popular in rural districts for supplying water for domestic purposes for a comparatively low water fall. _A UBydraulic Engine, utilizing pulsations in a closed pipe system has been proposed. The pulsations are imparted to the incompre ible water by a pumplike apparatus; the motor also resembles @ valvele pump. In this system there is no flow of water, the pulsations transmitting the energy. Its future however is doubtful since other power transmitting systems are more efiicient and convenient. NH), is a colorle liquid, B.P. 113°°5 C., formed by complex organic decomposition. It is heavier than and soluble in water, and at 0° C. forms colorle crystals. It reacts vigorously with the halogens and is a strong reducing agent. HYDROCARBONS. A large group of compounds composed of hydrogen and carbon combined in varying proportions. The three principal groups of hydrocarbons are known as (1) saturated (2) unsaturated, (8) hydrocarbons containing a ring structure. Saturated hydrccarbons are those in which all four valencies of the carbon atom are satisfied. They have the general formula Cn Hn + 2. The paraffins belong to this group, including marsh gas, CH, which is the simplest hydrocarbon known, and most of the constituents of petroleum oil. Unsaturated hydrocarbons, having the general formula CnHon, or CnHsn2, contain unsatisfied carbon bonds and will therefore unite directly with other elements, such as chlorine, without any disturbance of the hydrogen atoms in the molecule. One of the best known of the unsaturated hydrocarbons is acetylene, C2H2. Others are ethylene, C2H., propylene, C:He, butylene, C.H: The hydrocarbons of ring structure imclude a number of compounds of great commercial importance, among them being benzene, C.He, toluene, O7Hs, naphthalene, CioHs, anthracene, Cui. Combination of one type with another frequently occurs in nature, so that the number of natural hydrocarbons is enormous. Decaying vegetable and animal matter, under favorable conditions, gives rise to hydrocarbons, natural gas and coal gas consist largely of them, and petroleum and shale oils are made up almost entirely of a mixture of hydrocarbons of varying complexity.