The highly unsaturated esters from cod and herring oils were prepared in a similar manner; 1620 g. of the methyl esters from 2000 g. of cod oil gave 480 g. of bromides, containing 70.75% of bromine. These when debrominated gave 93 g. of esters; yield, 67.65%. 1875 g. of esters from 2200 g. of herring oil gave 517 g. of bromides, with a bromine content of 69.29%. These yielded 83 g. of esters, or 52.3%.

The highly unsaturated esters of menhaden oil were distilled thrice under diminished pressure, while those of cod and herring oils were distilled only once, on account of the small quantity available. For the second and third distillations of the menhaden oil esters, the fractions were introduced in order into the distilling flask by means of a sep-aratory funnel, the stem of which had been drawn out to a fine tip. All of the temperatures were corrected to 15 mm. pressure, including the stem correction for the thermometer. The last 4 fractions of the esters of cod oil showed abnormal values for all but molecular weight, due to accidental overheating. The analyses follow.

Table VII. The Constants Of The Fractionated Methyl Esters Of The Highly Unsaturated Fatty Acids Of Menhaden, Cod And Herring Oils, Prepared By Reduction Of The Polybromides Menhaden Oil, Distilled Thrice

Fraction

Range (15 mm.)

Wt. G.

M. m. wt. acids

Iodine no.

n20

Poly-bromide no.

Br

%

Mixed esters (215-250°)

307.9

368.5

1.4910

105.33

69.40

1

below 203°

9.5

322.0

260.6

1.4753

......

.....

2

203-213

30.0

274.1

334.8

1.4800

......

......

3

213-218

16.0

280.8

348.8

1.4860

94.67

68.62

4

218-223

22.0

284.7

359.4

1.4888

96.62

69.71

5

223-228

47.0

292.2

363.8

1.4907

101.9

69.78

6

228-233

35.5

298.1

372.8

1.4919

101.0

69.69

7

233-238

33.0

307.5

376.3

1.4950

101.21

70.45

8

238-243

31.0

315.8

379.2

1.4970

97.56

70.46

9

243-248

17.0

317.4

373.2

1.4980

76.02

70.48

10

248-255

11.0

324.7

357.9

1.4987

64.90

70.99

Cod oil, distilled once

Mixed esters (210-247°)

298.0

383.5

1.4912

125.8

70.4

1

below 213°

11.0

279.4

362.2

1.4865

104.0

68.70

2

213-218

11.0

286 7

369.8

1.4881

109.8

69.21

3

218-223

18.0

293.0

380.0

1.4895

113.0

69.56

4

223-228

11.5

303.3

305.9

1.4940

......

.....

5

228-233

4.0

307.3

277.9

1.4985

.....

.....

6

233-2.50

5.5

313.0

257.5

1.4992

....

.....

7

250-270

10.0

323.5

232.5

1.4993

.....

.....

Herring oil, distilled once

Mixed esters (215-250°)

299.2

373.9

1.4910

113.25

69.66

1

below 213°

6.0

277.8

354.0

1.4860

97.7

68.99

2

213-218

7.0

283.4

361.8

1.4873

101.1

68.81

3

218-223

9.0

286.0

366.3

1.4888

103.0

69.05

4

223-228

11.5

294.0

369.5

1.4900

111.0

69.45

5

228-233

16.5

299.0

376.0

1.4928

106.5

69.69

6

233-238

11.0

309.3

379.4

1.4960

102.0

70.12

7

238-245

4.5

315.0

372.0

1.4992

94.0

70.61

Menhaden oil, faction 2, redistilled

2a

180-195

9.0

266.8

316.5

1.4800

72.78

68.59

2b

195-205

7.5

274.5

333.7

1.4829

......

....

2c

205-212

5.5

282.7

344.7

1.4896

......

.....