Jan. i, 1880] 



NATURE 



209 



begin with, the name " stratus," which has ever been the 

 object of Poey's especial animadversion, was unluckily 

 applied by Howard himself to ground fog. The result 

 has been a curious condition of anarchy among the 

 followers of Howard's system up to the present day. The 

 predicament in which these observers have found them- 

 selves is this. One of the three primary cloud-names which 

 Howard introduced is never, if his system be rigidly 

 followed, to be applied to any object which most people 

 call a cloud at all. It must be admitted that a fog and a 

 cloud are, in structure, one and the same thing : a cloud 

 is a fog viewed from without, and a fog is a cloud viewed 

 from within. But it is precisely because a fog is, in this 

 sense, a cloud, and not a particular kind of cloud, that it 

 is objectionable in practice to apply to a fog a specific 

 cloud name. An observer may be for hours together 



enveloped in a fog of the form of which he can discover 

 nothing, except that the under surface necessarily follows 

 the contour of the earth's surface. In a classification 

 having reference to the shapes of clouds, it is undesirable 

 to give to such a phenomenon a technical name distinctive 

 of a special form of cloud. Prof. Poey pertinently says 

 " aucun observateur consciencieux nc voudra enregistrer 

 sous 1c nom de ' stratus ' un phe"nomene de brouillard." 

 On the other hand, a very large class of clouds, occurring 

 in every part of the globe, and in some parts actually the 

 predominant type, have possessed in Howard's terminology 

 no appellation at all, viz., the clouds, neither cumulus nor 

 cirrus, which extend themselves in a bed or layer, whose 

 vertical dimensions as compared with its horizontal are 

 very small. A certain number of observers have freely 

 applied the term " stratus" to this type of cloud. Others, 



Fig. 3. — " Mammato-cumulu 



perhaps more conservative, have created endless confusion 

 by bestowing the name "cirro-stratus" on all clouds of the 

 description to which we refer, while others again have 

 wrought similar havoc by a corresponding misapplication 

 of another of Howard's compounds " cumulo-stratus." 

 Finally, Prof. Hildebrandsson is driven to the revival of 

 the " strato-cumulus" of Kaemtz, as the title for the pre- 

 vailing winter-cloud of Northern Europe. Prof. Poey's 

 remedy for this state of things is to abolish the term 

 " stratus," and to apply to all clouds which lie in beds 

 the title " pallium." The effort has already proved par- 

 tially successful, for, owing to the defect in Howard's 

 system, "pallium" and its compounds have to some 

 extent replaced, at least among American meteorologists, 

 the "stratus" of Howard and its compounds. Ice- 

 clouds disposed in a sheet or layer are to receive the 

 name "pallio-cirrus" ; water-clouds the name] " pallio- 



cumulus.'' We think Prof. Poey's objection to the word 

 " stratus " as applied to a bed or layer of cloud some- 

 what ill-directed. The term (signifying "levelled,'' or 

 ''laid flat") is in itself quite as expressive as "pallium" 

 (which does not so much involve the idea of the hori- 

 zontal) ; and, however it may have been misapplied, 

 we suspect that it will yet prove possessed of too much 

 respectability to be summarily ejected. Prof. Poey would 

 retain, inconsistently as it appears to us, the compound 

 name "cirro-stratus," but we have always found it extremely 

 difficult to understand precisely what kind of cloud he 

 means to describe under this name, or to recognise with 

 any distinctness what is his idea of "nuagc stratine," 

 the clouds which he terms " stratified " baing rather what 

 most persons would call "striated.' Whenever cirrus 

 becomes sufficiently extended to form a veil or sheet, it„is 

 to receive the name "pallio-cirrus." " Cirro-stratus "Js 



