that this rim of India-rubber would bear a temperature of two hundred and seventy-eight degrees without charring; second, that it would not melt or soften at any heat; third, that, placed between blocks of ice and left out of doors all night, it would not stiffen in the least degree.  He had triumphed, and he knew it.  He tells us that he now “felt himself amply repaid for the past, and quite indifferent as to the trials of the future.”  It was well he was so, for his darkest days were before him, and he was still six years from a practicable success.  He had, indeed, proved that a compound of sulphur and India-rubber, in proper proportions and in certain conditions, being subjected for a certain time to a certain degree of heat, undergoes a change which renders it perfectly available for all the uses to which he had before attempted in vain to apply it.  But it remained to be ascertained what were those proper proportions, what were those conditions, what was that degree of heat, what was that certain time, and by what means the heat could be best applied.

The difficulty of all this may be inferred when we state that at the present time it takes an intelligent man a year to learn how to conduct the process with certainty, though he is provided, from the start, with the best implements and appliances which twenty years’ experience has suggested.  And poor Goodyear had now reduced himself, not merely to poverty, but to isolation.  No friend of his could conceal his impatience when he heard him pronounce the word India-rubber.  Business-men recoiled from the name of it.  He tells us that two entire years passed, after he had made his discovery, before he had convinced one human being of its value.  Now, too, his experiments could no longer be carried on with a few pounds of India-rubber, a quart of turpentine, a phial of aquafortis, and a little lampblack.  He wanted the means of producing a high, uniform, and controllable degree of heat,—­a matter of much greater difficulty than he anticipated.  We catch brief glimpses of him at this time in the volumes of testimony.  We see him waiting for his wife to draw the loaves from her oven, that he might put into it a batch of India-rubber to bake, and watching it all the evening, far into the night, to see what effect was produced by one hour’s, two hours’, three hours’, six hours’ baking.  We see him boiling it in his wife’s saucepans, suspending it before the nose of her teakettle, and hanging it from the handle of that vessel to within an inch of the boiling water.  We see him roasting it in the ashes and in hot sand, toasting it before a slow fire and before a quick fire, cooking it for one hour and for twenty-four hours, changing the proportions of his compound and mixing them in different ways.  No success rewarded him while he employed only domestic utensils.  Occasionally, it is true, he produced a small piece of perfectly vulcanized India-rubber; but upon subjecting other pieces to precisely the same process, they would blister or char.