592 



NA TURE 



[October 19, 1893 



many of them possess one qualification for success which 

 most men lack : they have, at all events, time at their 

 disposal. 



Do not let me be misunderstood. I am far from de- 

 siring that the students of Bedford College should leave 

 its walls impressed only with the importance of adding 

 to knowledge, and inclined to neglect other and, at least 

 as urgent duties. In my opinion, no man or woman can 

 afford to cultivate any one part of their nature to the 

 exclusion of the others. Sad stories have sometimes 

 been told of homes in which work has been done which 

 will never be forgotten, but done at the cost of all the 

 brightness and happiness which are usually associated 

 with the name of home. This want of the sense of 

 proportion, of the relative importance of different claims, 

 casts a shadow on the brightest intellectual fame. I 

 am not asking for such sacrifices. I believe that in 

 general they are absolutely unnecessary. But where 

 theover-mastering curiosity of the born investigator exists, 

 it will find a career, which may indeed involve self- 

 sacrifice, but which need make no harsh demand on 

 others. 



There are, to my knowledge, at the present moment 

 a large class of men who are living more hardly than 

 they otherwise might live, who are cheerfully surrender- 

 ing days which might be given to pleasure or to money- 

 making, and are spending laborious nights, simply be- 

 cause they are impelled by the desire to add some- 

 thing to the pile of knowledge which our race is through 

 the centuries accumulating. It cannot but be that if the 

 same spirit animated the women and girls of this 

 generation, many would be found among them who, 

 without neglecting any duty, would work with the same 

 energy for the same object. 



It is possible that some of my hearers may accuse me 

 of holding up an impossible ideal. My answer is that 

 the founders of Bedford College held up to their genera- 

 tion an ideal which was then regarded as impossible 

 but which has nevertheless been realised. Women, if 

 they please, can now be educated to the same high level 

 as men. I in turn venture to hold up to you an ideal at 

 which Bedford College should aim in the future. It is 

 that it should be known as a place of learning as well 

 as a place of education, as a place where not only is 

 the number of those who know added to, but where 

 knowledge itself is increased. 



THE INNER STRUCTURE OF SNOiV 

 CRYSTALS. 



THE ice and snow crystals photographed and described 

 by me ' may be referred to the following types. 



I. Crystals developed in the direction of the vertical 

 axis, (a) Hexagonal prisms, [b) Bottle-shaped^prisms. 

 (f) Needles. 



II. Tabular crystals, (li) Hexagonal tables, (b) Stel- 

 lated tables, {c) Dendritic tables. 



III. Crystals equally developed along the vertical and 

 lateral axes. 



Among these groups, types I. (c) and III. are in no way 

 different from the ordinary hexagonal crystals, and 

 accordingly of less general interest. The former, 1. (t), is 

 common in drifting snow ; to the latter belong the sharp 

 edged hexagonal prisms without annties, which compose 

 the under layers of the snow covering. They are never 

 found among the snowflakes, and are accordingly origin- 

 ated by a molecular change in the snow covering. Type 

 1 1, (c) comprises the relatively large dendritic crystals with 

 complicated ramifications which are visible even to the 

 naked eye as handsome regular stars. They have been 

 figured and described by several observers, from Claus 

 Magnus and Keppler to Scoresby and Glaisher, and I 



1 " Geol. Foren. i Stockh." Forh. Bd. 15, p. 146. 



NO. 1251, VOL. 48] 



shall therefore not dwell upon them in the present paper. 

 Of the remaining extremely interesting types (I. a, b ; II. 

 a, b), which, owing to their microscopic dimensions, have 

 hitherto received no attention from men of science, I 

 give a brief description. 



I. {a) Hexagonal Piistiu. 

 Fig. I shows the commonest type. It is bounded by 

 the basal planes and the hexagonal prism, and of interest 

 on account of the hour-glass shaped cavities invariably 

 present within the crystal. These are, as shown by the 

 figure, widest near the two basal planes, where they are 

 bounded by a negative hexagonal prism ; nearer the 



^FlG. I. 



centre they contract again to expand in the form of two 

 bulbs, elongated to points and confluent. The shape of 

 the cavities is almost always the same. Crystals of this 

 type are very small (about o'S mm. long), and the inner 

 structure only distinguishable under the microscope. 

 They are common in drifting snow. 



I. (b) Bottle-shaped Prisms. 

 The bottle-shaped crystals of elongated^ prismatic 

 form have the appearance shown in Fig. 2. Like 

 the crystals of the preceding type, they are bounded 

 by an hexagonal prism and the basal plane ; but 

 one end is pointed, and the crystals accordingly 

 hemimorphic. The bottle-shaped crystals also contain 



Fig 2. 



I cavities, less regular, however, than those in the crystals 

 i of the preceding type. The following circumstance 

 I attaches a special interest to these crystals. On Feb- 

 ruary 8 there was a rather sparse fall of agglomerations of 

 I bottle-shaped crystals such as are shown in Fig. 2. The 

 I cavities in these crystals proved under the microscope to 



