There has been a very marked change in the character of ketchup since the transition from the preservative to non-preservative goods, not only microscopically, but also in composition. Formerly, there were very many brands of thin liquid ketchup, showing little concentration of pulp, very low in sugar, and having only small quantities of vinegar; the standard was bulk rather than quality. The microscopic examination also showed that the product had frequently undergone change before and after preparation. Recent examinations show that there has been a very marked improvement; that the body is decidedly heavier, more sugar and vinegar are used, the tissue is cleaner, and there are fewer organisms present, also that the difference in composition in preservative and non-preservative ketchup is small, whereas, formerly it was marked. The variations found in ketchup of rather recent examination show in the non-preservative kind the specific gravity varied between 1.091 and 1.177; the solids between 19 and 37 per cent; the salt between 2 and 4 per cent; sugar between 12 and 29 per cent; and volatile acids between .54 and 1.24 per cent. In the preservative kind, the specific gravity ranged from 1.032 to 1.120; the solids from 9.23 to 28 per cent; salt, 1.48 to 3.4 per cent; sugar, 4.95 to 16.9 per cent; and volatile acidity, .16 to .64 per cent. As a class they averaged lower in concentration of tomato and in sugar and vinegar, though if proper sterilization had been used, some of them would have kept without difficulty. In experimental work it was found that a ketchup concentrated so that when finished it showed an added sugar content of 15 per cent or more, a total acidity of 1.2 per cent, and a specific gravity of 1.120 or more, that it would keep. To obtain a total acidity of 1.2 per cent means the addition of about .4 to .6 per cent acidity in the vinegar used. However, there are brands of ketchup on the market which keep well after being opened and which have a total acidity of less than 1.0 per cent. The manufacturer can use the following as a starting point for non-preservative ketchup; pulp, 100 gallons; sugar, 60 pounds; salt, 8 pounds; vinegar, 100 grain, 2 gallons; spice to flavor; and concentrate to 50 to 55 gallons. ------------------------------------------------------------------------ MICROSCOPIC EXAMINATION.