76
GORDON A. RILEY
organic compounds with molecular weights in excess of 300. This
much was well documented. Their hypothesis that particle formation
involves the compression of monomolecular surface film into a polymolecular complex seemed at that time to be the simplest explanation
of further events. However, Garrett (1968) has questioned whether film
compression occurs to a significant degree, and other findings suggest
that processes acting at the sea surface are more complicated than was
originally supposed. Wangersky ( 1965) believed that adsorption of
organic matter on crystals of sea salts was an important feature of the
process, and apparent stabilization of the crystals indicated that the
organic " skin " was relatively impermeable. Further evidence supporting these results was the demonstration by Chave ( 1 965, 1968) and
Suess (1968) that calcium carbonate can be protected from solution by
absorbed organic coatings and that naturally occurring particles frequently contain calcite crystals.
Papers by Garrett (1964), Jarvis (1965), Jarvis et al. (1967) and
several others by this group of investigators have examined the physical
and chemical characteristics of surface films in the sea, using a collecting
device which picks up the upper 0.15 mm of water and associated surface film materials. The materials were used for chemical analysis and
experiments on physical properties. Garrett (1964) reported the presence of free fatty acids, fatty acid esters and alcohols, and probably
nonpolar hydrocarbons. Small quantities of carbohydrates and polypeptides or amino acids (as determined by anthrone and ninhydrin
reagents, respectively) were reported. These latter materials were
passed through a Sephadex column which had an exclusion limit of
about 5 000 molecular weight units. The majority of the carbohydrate
material was in the high molecular weight fraction, and most of the
ninhydrin reactive substances had molecular weights of less than
5 000.
Jarvis (1965) reported that surface active material can be transported to the surface and collected there by either bubbling or stirring.
Jarvis et al. (1967) found in experimental studies of film pressure that
the calculated average film thickness of some of their samples was a s
much as 300& more than an order of magnitude larger than the
calculated thickness of a monomolecular film. They concluded that
there is a selective process involved in which initially all of the organic
materials arriving at a clean water surface would be adsorbed at the
interface, but with further addition only the more surface-active molecules such as long-chain fatty acids would remain strongly adsorbed,
and more weakly adsorbed and water soluble molecules would be
displaced.
GORDON A. RILEY
organic compounds with molecular weights in excess of 300. This
much was well documented. Their hypothesis that particle formation
involves the compression of monomolecular surface film into a polymolecular complex seemed at that time to be the simplest explanation
of further events. However, Garrett (1968) has questioned whether film
compression occurs to a significant degree, and other findings suggest
that processes acting at the sea surface are more complicated than was
originally supposed. Wangersky ( 1965) believed that adsorption of
organic matter on crystals of sea salts was an important feature of the
process, and apparent stabilization of the crystals indicated that the
organic " skin " was relatively impermeable. Further evidence supporting these results was the demonstration by Chave ( 1 965, 1968) and
Suess (1968) that calcium carbonate can be protected from solution by
absorbed organic coatings and that naturally occurring particles frequently contain calcite crystals.
Papers by Garrett (1964), Jarvis (1965), Jarvis et al. (1967) and
several others by this group of investigators have examined the physical
and chemical characteristics of surface films in the sea, using a collecting
device which picks up the upper 0.15 mm of water and associated surface film materials. The materials were used for chemical analysis and
experiments on physical properties. Garrett (1964) reported the presence of free fatty acids, fatty acid esters and alcohols, and probably
nonpolar hydrocarbons. Small quantities of carbohydrates and polypeptides or amino acids (as determined by anthrone and ninhydrin
reagents, respectively) were reported. These latter materials were
passed through a Sephadex column which had an exclusion limit of
about 5 000 molecular weight units. The majority of the carbohydrate
material was in the high molecular weight fraction, and most of the
ninhydrin reactive substances had molecular weights of less than
5 000.
Jarvis (1965) reported that surface active material can be transported to the surface and collected there by either bubbling or stirring.
Jarvis et al. (1967) found in experimental studies of film pressure that
the calculated average film thickness of some of their samples was a s
much as 300& more than an order of magnitude larger than the
calculated thickness of a monomolecular film. They concluded that
there is a selective process involved in which initially all of the organic
materials arriving at a clean water surface would be adsorbed at the
interface, but with further addition only the more surface-active molecules such as long-chain fatty acids would remain strongly adsorbed,
and more weakly adsorbed and water soluble molecules would be
displaced.