(_b_) _By calculation from the specific gravity of the pulp._—There is a very exact relation between the specific gravity of pulp (determined by the method given above) and the per cent of total solids as determined by drying. The solids corresponding to pulps of various specific gravities are given in Table 5, or may be obtained from the following formula which is derived from the same table: Per cent Solids = 228 (sp. gr. of pulp - 1.000) + 19.1 (sp. gr. of pulp - 1.015). 2. BY THE EXAMINATION OF THE FILTRATE If a sample of pulp of considerable size be thrown on a folded filter, a filtrate is obtained whose composition has a definite relation to that of the whole pulp. (_a_) _By drying._—The per cent of solids in the filtrate may be determined by drying _in vacuo_ at 70° C, or under atmospheric pressure at the temperature of boiling water. As in the case of the drying of pulp, a constant relation is found to exist between the per cent of solids in the filtered liquor as determined by drying _in vacuo_ at 70° C., and the per cent of solids as determined by drying at atmospheric pressure at the temperature of boiling water. The per cent of solids in the filtrate obtained by drying at atmospheric pressure, multiplied by 1.125, gives the per cent of solids obtained by drying _in vacuo_. This relation is shown in detail in Table 5. TABLE 2.—_Composition of Whole Tomato Pulps_ ======================================= | Composition of pulps | +-------+---------------------+ |Sp. gr.| Total |Insoluble | Sample | at | solids(a)| solids | No. |20° C. | | | | | | | | | | | --------+-------+----------+----------+ | |_Per cent_|_Per cent_| 1290 | 1.0252| 5.94 | 0.66 | 1291 | 1.0273| 6.54 | 0.78 | 1292 | 1.0234| 5.50 | 0.80 | 1293 | 1.0293| 7.02 | 0.74 | 1294 | 1.0272| 6.48 | 0.69 | | | | | 1295 | 1.0361| 8.67 | 0.95 | 1296 | 1.0380| 9.00 | 1.06 | 1297 | 1.0465| 11.20 | 1.19 | 1299 | 1.0417| 10.07 | 1.23 | 1300 | 1.0322| 7.70 | 0.93 | | | | | 1301 | 1.0312| 7.36 | 0.91 | 1302 | 1.0310| 7.45 | 0.91 | 1303 | 1.0340| 8.17 | 0.91 | 1304 | 1.0292| 6.88 | 0.88 | 1305 | 1.0371| 9.03 | 1.19 | | | | | 1306 | 1.0370| 8.95 | 0.98 | 1307(b)| 1.0328| 7.86 | 1.01 | 1481 | 1.0449| 10.82 | | 1482 | 1.0444| 10.83 | | 1483 | 1.0464| 11.21 | | | | | | 1484 | 1.0423| 10.27 | | 1485 | 1.0347| 8.55 | | 1477(c)| 1.0610| 13.86 | | 1479 | 1.0411| 10.00 | 1.21 | 1486 | 1.0169| 4.34 | 0.62 |