April i, 1904.] 



THE INDIA RUBBER WORLD 



243 



THE "PICRADENIA" AND THE GRAPHIC CHART. 



THREE United States patents granted recently — two of 

 them to Myron G. Brownell, and one to Richard A. 

 Leigh, both at present of Denver, Colorado — may prove 

 of no little interest to rubber men. 

 The first patent granted to Brownell, No. 752,951,1s for a 

 Rubber-like Gum. In this he states clearly that he has invented 

 — really invented — this gum. Some finicky people might claim 

 that he merely extracted the gum, but let his words stand- 

 The genesis of his invention appears to be the discovery in his 

 locality of a plant or shrub known (not widely) as the " Colo- 



[1] Picrad,nia\ [2] Plant ground 



jioribunda or suitably 



utilis. prepared. 



Water. [6] Pulp subjected to coin- 

 Pulp pressive rubbing action. 



Gum 17] Fiber. 



rado rubber plant." This, according to a botanist to whom 

 it was submitted, turns out to be the Picradenia Jioribunda 

 utilis, and he adds that it contains considerable quantities of 

 rubber in its roots. This plant is not to be confused with the 

 Picradenia Richardsoni, the Picradenia Brownelli.or, the Picra- 

 denia Leighhigh valleyi, 



Mr. Brownell takes the plant by force, dries it, powders it, 

 puts it in a solution of, say benzine, to which is added a few 

 drops of alcohol, which dissolves the rubber-like gum. The 



I i/mtutel ttr \ 



[1] Picradenia [2] Plant ground [3] Pulp formed by mix- [4] Hydrocarbon or 

 fioiibunda or suitably ing prepared plant other suitable 



utilis. prepared. and hydrocarbons. product. 



f5] Separation of [6] Distillation [7] Residue [8] Condensed 

 plant from fiber. of liquid. orgum. solvent. 



FIQ. 2. 



liquid is then separated from the plant fiber, is later subjected 

 to distillation, leaving the gum in one receptacle and the sol- 

 vent in another. The subjoined drawing or graphic chart 

 (Fig. i) graphically indicates the various steps of the process. 

 Further on Mr. Brownell says that while the process that he 

 describes of recovering the gum has been found efficient, it is 

 to be understood that he may employ any process which will 

 serve to produce the gum from the plant Picradenia Jioribunda 

 utilis. Therefore hands off from the Picradenia— and don't 

 monkey with the utilis. 



After affixing his signature in the presence of two witnesses, 

 Mr. Brownell proceeds to spring on an awestruck world patent 

 No. 752,952. Here he has a graphic chart (Fig. 2) as well as a 

 picture of a machine, used as an aid in inventing the rubber- 

 like gum. This process consists of the grinding of the plant, 

 its mixture with water until a pulp is formed, a subjection to 

 compressive rubbing action, and the separation of the gum and 

 fiber by washing, and this delivers the gum pure, which is al- 

 ways a desideratum. The witnesses having come in about this 

 time, Myron G. affixed his signature, and we turn to the third 

 patent. 



This is numbered 752,988 and is granted to Leigh, who as- 

 signs it to the Western Rubber Co., of Denver, Colorado. It is 

 evident from the beginning that the graphic chart has got in 

 its work on this inventor also, for he springs one on the reader 

 at the first jump (Fig. 3). His invention, however, deals with 

 the utilization of the gum; in other words he attends to the 



Sheets cut up or 



otherwise suitably 



prepared for 



vulcanizing. 



re] 



Subjected 

 to heat. 

 FIG. 3. 



utilis. Briefly described, he mixes it with " sulfur." sheets it, 

 cuts it up or otherwise suitably prepares it for vulcanizing, and 

 vulcanizes it ! He makes hard or soft goods. He cures in dry 

 or wet heats — and, like Brownell, he too, affixes his signature. 



But what of the " Salad rubber plant ? " 



For years both of these discoverers must have known the Lac • 

 tuca sativa, which contains rubber, not in its roots but in its 

 broad succulent leaves. It is even more of a utilis than the 

 Picradenia, for its leaves are edible. That it is commonly 

 known as " lettuce " in no way interferes with its value as a 

 possible rubber producer, orat least a producer of a rubber-like 

 gum. Further than this, if edible solvents were used after the 

 mixing chamber were reached, the product might follow one 

 line of treatment and emerge as Para rubber, or another and be 

 marketed as lettuce salad. In order effectually to protect such 

 a valuable process and interest sufficient capital to do the busi- 

 ness on a large scale, it would be well to apply for a patent, il- 

 lustrated by the subjoined graphic chart (Fig. 4.) 



