With 2:2′-dipyridyl as reagent for reducible and total iron, determinations were made on samples from the western English Channel at midwinter 1946–47, at the time of the maximum of phosphate, and also in July 1936.The midwinter results have been treated statistically and the errors of analysis assessed.Unlike phosphate and nitrate, much of the inorganic iron occurs as particles of fair size, distributed at random in the water. In winter there is no statistically significant difference between the total iron content of samples drawn from 0·5,5,25 and 50 m. depth, the grand mean and standard deviation for the whole area being 0·25 ± o·11 mg.-atom/m.3. The reducible iron for the same depth range and area was 0·19 ± 0·14 mg.-atom/m.3. There appears to be about 0·06mg.-atom/m.3 of iron which is reasonably highly dispersed and not determinable until the water has been oxidized with bromine.In the bottom layers of water, although the reducible fraction differs little from the overlying layers, the total iron shows a very much greater mean value and variance.The very low content of total and reducible iron and of particulate ferric phosphate in bottom water at a position 49° 30′ N., 5° 00′ W. has been provisionally attributed to removal by a dense bed of suspension feeders, possibly the mollusc Pinna.By a statistical examination of the analytical results it has been deduced that the particulate fraction in the upper 50 m. was distributed on an average amongst about 45 particles per litre, each containing about 0·24μg. Fe and with a diameter of about 160μ. This result has been compared with data on the distribution of iron in plankton organisms.As a statistical average waters richer in phosphate were also richer in total iron, the atomic ratio Fe/P being about 0·57.In July 1936 the ‘elegans’ water to the westward was much richer in both phosphate and total iron than the more eastern mixed water containing Sagitta setosa. The results agree well with the conclusions drawn from the cruises at midwinter 1946–47.In 1933–34 concentration of iron was frequently observed in the surface layers; in 1946–47 it was not. In the earlier work the surface film was always cut and included in the sample, in the later it was not. The probable amount of a surface unimicellar film of electropositive unprotected ferric hydroxide has been calculated and agrees well with observation.Particulate ferric phosphate was found to the extent of about 0·06 mg.- mols/m.3 This appears to increase towards the bottom.The success of the work at Newlyn in January 1947 owes much to the willing co-operation of Capt. Creese and the crew of R.V. Sabella under very adverse weather conditions. To Mr P. G. Corbin grateful thanks are due for undertaking single-handed the supervision of all the scientific work at sea on stations never more than two hours apart for two or three days on end. The statistical development would not have been possible without the unstinted assistance of Mr G. M. Spooner.

中文翻译：

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西英吉利海峡水域铁的分布

用 2:2'-联吡啶作为还原铁和总铁的试剂，测定了 1946-47 年冬至 1936 年 7 月英吉利海峡西部的样品，当时正值磷酸盐含量最高的时候，也是在 1936 年 7 月。进行了统计处理并评估了分析错误。与磷酸盐和硝酸盐不同，大部分无机铁以大小适中的颗粒形式出现，随机分布在水中。在冬季，从0·5、5、25和50 m处抽取的样品的总铁含量在统计学上没有显着差异。深度，整个区域的总平均值和标准偏差为 0·25 ± o·11 mg.-atom/m。3. 相同深度范围和面积的可还原铁为0·19 ± 0·14 mg.-atom/m。3. 似乎有大约 0·06mg.-atom/m。3铁是相当高度分散的，直到水被溴氧化后才能测定。在水的底层，尽管可还原部分与上层的差异很小，但总铁的平均值和方差要大得多。在北纬 49° 30'，西经 5° 00' 的底部水中，总铁和可还原铁以及颗粒磷酸铁的含量非常低，暂时归因于悬浮进料器密集床的去除，可能是软体动物耳廓.通过对分析结果的统计检验，推断出上层50 m处的颗粒分数。平均分布在每升约 45 个颗粒中，每个颗粒含有约 0·24μg。Fe，直径约160μ。该结果已与浮游生物中铁的分布数据进行了比较。作为统计平均，富含磷酸盐的水域也富含总铁，原子比 Fe/P 约为 0·57。1936 年 7 月，“线虫”向西的水比东部的混合水含有更多的磷酸盐和总铁矢车菊. 结果与 1946-47 年冬至的巡航得出的结论非常吻合。在 1933-34 年，经常在表层观察到铁浓度；在 1946-47 年不是这样。在早期的工作中，表面薄膜总是被切割并包含在样品中，而在后来的工作中则没有。已计算出带正电的无保护氢氧化铁表面单胶束膜的可能量，与观察结果吻合良好。发现磷酸铁颗粒的含量约为 0·06 mg.- mols/m。3这似乎在向底部增加。1947 年 1 月在 Newlyn 的工作的成功很大程度上归功于船长 Creese 和 RV 船员的愿意合作萨贝拉在非常恶劣的天气条件下。感谢 PG Corbin 先生，感谢他单枪匹马地监督所有海上科学工作，在站上的时间间隔不超过两小时，连续两三天。如果没有 GM Spooner 先生的无私帮助，统计数据的发展是不可能的。