What is claimed is:1. A spray apparatus which comprises:(a) a nozzle through which a liquid-solid slurry is discharged under pressure;(b) a first surface for intercepting and initially deflecting the path of nozzle discharge incident thereon; and,(c) a second surface for intercepting and redeflecting initially deflected nozzle discharge incident thereon.2. The spray apparatus of claim 1 which further comprises:(d) a gas injecting zone for receiving liquid-solid slurry under a first positive pressure and a gas under a higher second positive pressure, at least a portion of the gas entering into and combining with the liquid-solid slurry prior to discharge from the zone through the nozzle.3. The spray apparatus of claim 2 wherein the nozzle is an open nozzle.4. In an apparatus for froth flotation separation of the components of a slurry having particulate matter therein, said apparatus including a flotation tank, a spray means for directing a spray of slurry at the surface of liquid within the flotation tank forming a froth thereon and means for removing froth from the flotation tank, wherein the improvement comprises a spray apparatus in accordance with claim 3.5. In an apparatus for froth flotation separation of the components of a slurry having particulate matter therein, said apparatus including a flotation tank, a spray means for directing a spray of slurry at the surface of liquid within the flotation tank forming a froth thereon and means for removing froth from the flotation tank, wherein the improvement comprises a spray apparatus in accordance with claim 3.6. The spray apparatus of claim 1 wherein the nozzle is an open nozzle.7. In an apparatus for froth flotation separation of the components of a slurry having particulate matter therein, said apparatus including a flotation tank, a spray means for directing a spray of slurry at the surface of liquid within the flotation tank forming a froth thereon and means for removing froth from the flotation tank, wherein the improvement comprises a spray apparatus in accordance with claim 6.8. In an apparatus for froth flotation separation of the components of a slurry having particulate matter therein, said apparatus including a flotation tank, a spray means for directing a spray of slurry at the surface of liquid within the flotation tank forming a froth thereon and means for removing froth from the flotation tank, wherein the improvement comprises a spray apparatus in accordance with claim 1.9. A method for the froth flotation separation of the components of a liquid-solid slurry which comprises:(a) discharging a liquid-solid slurry under pressure through a nozzle upon the surface of a liquid forming a froth thereon, said nozzle being provided with a first surface for intercepting and initially deflecting the path of nozzle discharge incident thereon and a second surface for intercepting and redeflecting initially deflected nozzle discharge incident thereon whereby the velocity of the nozzle discharge is significantly reduced; and,(b) removing froth from the liquid surface.10. The froth flotation method of claim 9 wherein prior to discharge of liquid-solid slurry in step (a), the method further comprises:(c) introducing liquid-solid slurry to a gas injecting zone under a first positive pressure; and,(d) introducing a gas under a higher second positive pressure into liquid-solid slurry present in the gas injecting zone whereby at least a portion of the gas enters into and combines with the liquid-solid slurry in said zone.11. The froth flotation method of claim 10 wherein the liquid-solid slurry is water-containing coal particulate, the gas is air and the liquid is water.12. The froth flotation method of claim 11 wherein the coal to water ratio is from about 1:25 to about 1:2 parts by weight.13. The froth flotation method of claim 12 wherein from about 80% of the coal particles are of -200 mesh in size (Taylor Standard Screen Size).14. The froth flotation of claim 11 wherein the particle size of the coal is from about -10 to about 500 mesh.15. The froth flotation method of claim 11 wherein the coal slurry is admixed in an aqueous medium with a surface treating mixture comprising a polymerizable monomer, a polymerization catalyst and a liquid organic carrier, thereby rendering said coal hydrophobic and oleophilic.16. The froth flotation method of claim 11 wherein the coal slurry is sprayed upon the surface of the water through an open spiral nozzle.17. The froth flotation method of claim 9 wherein the liquid-solid slurry is water-containing coal particulate.18. The froth flotation of claim 17 wherein the particle size of the coal is from about -10 to about 500 mesh.19. The froth flotation method of claim 18 wherein from about 80% of the coal particles are of -200 mesh in size (Taylor Standard Screen Size).20. The froth flotation method of claim 17 wherein the coal to water ratio is from about 1:25 to about 1:2 parts by weight.21. The froth flotation method of claim 17 wherein the coal slurry is admixed in an aqueous medium with a surface treating mixture comprising a polymerizable monomer, a polymerization catalyst and a liquid organic carrier, thereby rendering said coal hydrophobic and oleophilic.22. The froth flotation method of claim 17 wherein the coal slurry is sprayed upon the surface of the water through an open spiral nozzle.