Gibbs’ Rotary Spade. 
This implement is designed to serve the same pur¬ 
pose as Samuelson’s Digging Machine, and is more 
simple in its construction. The Rotary Spade is the 
invention of Mr. L. Ii. Gibbs, of Washington, D. C., and 
is now exhibiting at the Crystal Palace. It is compos¬ 
ed of two cast-iron circular plates, about two inches 
apart, and working between them are eight stout, nar¬ 
row wrought-iron teeth, curved somewhat like the old- 
fashioned cultivator teeth. These teeth are hung, and 
have a trigger to throw them out as the machine re¬ 
volves. A yoke of oxen are sufficient to draw the 
machine, and as it progresses each tooth in succession 
is pressed into the earth by the weight of the machine, 
and, when the weight falls upon the trigger, the tooth 
is thrown out with its load of earth, which is thus mix¬ 
ed and pulverized as thoroughly as if forked over. 
The two wheels cut a furrow about two feet wide and 
nine inches deep, which can be increased to any de¬ 
sired width and depth. It requires no holding, yet is 
provided with handles so fixed as to throw the machine 
out of the ground. 
The cut which we take from the Peoples’ Journal, 
is an accurate representation of the implement. Now 
that the importance of fine tilth is so generally under¬ 
stood, the advantage of an implement of this sort will 
be readily seen. Where land has been plowed in the 
fall, preparatory to spring sowing or planting, the Ro¬ 
tary Spade passed over the ground in the spring would 
put the soil in fine condition for a crop. 
Valparaiso Squash. 
Messrs. Editors. :—I raised a notable quantity of 
Valparaiso Squash, last season, on a small piece of 
ground —I should think half a ton’s weight from eight 
or ten hills. They grow to a large size, as the speci¬ 
mens on exhibition at the different County and State 
Fairs abundantly prove. My hogs fed upon them 
with great avidity, and as they are obviously a more 
nutritious kind of food for stock than pumpkins, I have 
been induced to believe they might be substituted for 
the latter in field cultivation, to advantage. With suit¬ 
able eare they must be very much more productive, 
and of richer flavor, as they are without doubt. It 
seems to me that Squashes are to he preferred to the 
old Conneticut staple. For culinary purposes there is 
no comparision between the two. I do not mean 
that Squashes can be planted among corn, where 
pumpkins never should he if there is a good stand; 
doubtless it would be necessary to give them full and 
exclusive possesion. I think I shall make a trial next 
year of a field crop of this species of Squash, and may 
communicate the result, if any of your readers should 
feel interested therein. V. W. Dec., 1853. 
Shell Marl, &c. 
What is the comparative value of shell marl as a fer¬ 
tilizer after having been exposed to the air and frost 
one season, in comparison with the same bulk of ash¬ 
es,. lime, muck, poudrette or super-phosphate of lime, or 
compost 1 
Where can Woodbury’s corn and plaster drill plan¬ 
ter be obtained, and what is the price ? 
Is sulphate of soda (glauber salts) of any practical 
utility, and economical, mixed with ashes as a fertil- 
zer 1 An answer to these questions will much oblige 
II. S- Felchville , Vermont. 
Shell marl is about the same in character and effect 
as lime, where the two are in a condition to be equally 
intermixed with the soil. Exposure to the frost of a 
winter does not effect shell marl, except it may in some 
instances render the marl more friable, and consequent¬ 
ly better for even application and thorough intermixture. 
It is difficult to compare its value to that of other ma¬ 
nure, as without other fertilizers, it would be of no val-' 
ue, and its effect would not be felt on soils already well 
supplied with lime. On the other hand in extreme 
caes, and where circumstances have been most favor¬ 
able, it has doubled the product of the land. The best 
